chrome/browser/about_flags.cc

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "chrome/browser/about_flags.h"
   6
   7 #include <algorithm>
   8 #include <iterator>
   9 #include <map>
  10 #include <set>
  11 #include <utility>
  12
  13 #include "ash/ash_switches.h"
  14 #include "base/command_line.h"
  15 #include "base/memory/singleton.h"
  16 #include "base/strings/string_number_conversions.h"
  17 #include "base/strings/utf_string_conversions.h"
  18 #include "base/values.h"
  19 #include "cc/base/switches.h"
  20 #include "chrome/browser/flags_storage.h"
  21 #include "chrome/common/chrome_content_client.h"
  22 #include "chrome/common/chrome_switches.h"
  23 #include "components/nacl/common/nacl_switches.h"
  24 #include "content/public/browser/user_metrics.h"
  25 #include "extensions/common/switches.h"
  26 #include "grit/chromium_strings.h"
  27 #include "grit/generated_resources.h"
  28 #include "grit/google_chrome_strings.h"
  29 #include "media/base/media_switches.h"
  30 #include "ui/base/l10n/l10n_util.h"
  31 #include "ui/base/ui_base_switches.h"
  32 #include "ui/gfx/switches.h"
  33 #include "ui/gl/gl_switches.h"
  34 #include "ui/keyboard/keyboard_switches.h"
  35 #include "ui/message_center/message_center_switches.h"
  36 #include "ui/surface/surface_switches.h"
  37
  38 #if defined(USE_ASH)
  39 #include "ash/ash_switches.h"
  40 #endif
  41
  42 #if defined(OS_CHROMEOS)
  43 #include "chromeos/chromeos_switches.h"
  44 #include "third_party/cros_system_api/switches/chrome_switches.h"
  45 #endif
  46
  47 using content::UserMetricsAction;
  48
  49 namespace about_flags {
  50
  51 // Macros to simplify specifying the type.
  52 #define SINGLE_VALUE_TYPE_AND_VALUE(command_line_switch, switch_value) \
  53     Experiment::SINGLE_VALUE, \
  54     command_line_switch, switch_value, NULL, NULL, NULL, 0
  55 #define SINGLE_VALUE_TYPE(command_line_switch) \
  56     SINGLE_VALUE_TYPE_AND_VALUE(command_line_switch, "")
  57 #define ENABLE_DISABLE_VALUE_TYPE_AND_VALUE(enable_switch, enable_value, \
  58                                             disable_switch, disable_value) \
  59     Experiment::ENABLE_DISABLE_VALUE, enable_switch, enable_value, \
  60     disable_switch, disable_value, NULL, 3
  61 #define ENABLE_DISABLE_VALUE_TYPE(enable_switch, disable_switch) \
  62     ENABLE_DISABLE_VALUE_TYPE_AND_VALUE(enable_switch, "", disable_switch, "")
  63 #define MULTI_VALUE_TYPE(choices) \
  64     Experiment::MULTI_VALUE, NULL, NULL, NULL, NULL, choices, arraysize(choices)
  65
  66 namespace {
  67
  68 const unsigned kOsAll = kOsMac | kOsWin | kOsLinux | kOsCrOS | kOsAndroid;
  69 const unsigned kOsDesktop = kOsMac | kOsWin | kOsLinux | kOsCrOS;
  70
  71 // Adds a |StringValue| to |list| for each platform where |bitmask| indicates
  72 // whether the experiment is available on that platform.
  73 void AddOsStrings(unsigned bitmask, ListValue* list) {
  74   struct {
  75     unsigned bit;
  76     const char* const name;
  77   } kBitsToOs[] = {
  78     {kOsMac, "Mac"},
  79     {kOsWin, "Windows"},
  80     {kOsLinux, "Linux"},
  81     {kOsCrOS, "Chrome OS"},
  82     {kOsAndroid, "Android"},
  83     {kOsCrOSOwnerOnly, "Chrome OS (owner only)"},
  84   };
  85   for (size_t i = 0; i < ARRAYSIZE_UNSAFE(kBitsToOs); ++i)
  86     if (bitmask & kBitsToOs[i].bit)
  87       list->Append(new StringValue(kBitsToOs[i].name));
  88 }
  89
  90 // Convert switch constants to proper CommandLine::StringType strings.
  91 CommandLine::StringType GetSwitchString(const std::string& flag) {
  92   CommandLine cmd_line(CommandLine::NO_PROGRAM);
  93   cmd_line.AppendSwitch(flag);
  94   DCHECK(cmd_line.argv().size() == 2);
  95   return cmd_line.argv()[1];
  96 }
  97
  98 // Scoops flags from a command line.
  99 std::set<CommandLine::StringType> ExtractFlagsFromCommandLine(
 100     const CommandLine& cmdline) {
 101   std::set<CommandLine::StringType> flags;
 102   // First do the ones between --flag-switches-begin and --flag-switches-end.
 103   CommandLine::StringVector::const_iterator first =
 104       std::find(cmdline.argv().begin(), cmdline.argv().end(),
 105                 GetSwitchString(switches::kFlagSwitchesBegin));
 106   CommandLine::StringVector::const_iterator last =
 107       std::find(cmdline.argv().begin(), cmdline.argv().end(),
 108                 GetSwitchString(switches::kFlagSwitchesEnd));
 109   if (first != cmdline.argv().end() && last != cmdline.argv().end())
 110     flags.insert(first + 1, last);
 111 #if defined(OS_CHROMEOS)
 112   // Then add those between --policy-switches-begin and --policy-switches-end.
 113   first = std::find(cmdline.argv().begin(), cmdline.argv().end(),
 114                     GetSwitchString(chromeos::switches::kPolicySwitchesBegin));
 115   last = std::find(cmdline.argv().begin(), cmdline.argv().end(),
 116                    GetSwitchString(chromeos::switches::kPolicySwitchesEnd));
 117   if (first != cmdline.argv().end() && last != cmdline.argv().end())
 118     flags.insert(first + 1, last);
 119 #endif
 120   return flags;
 121 }
 122
 123 const Experiment::Choice kEnableCompositingForFixedPositionChoices[] = {
 124   { IDS_GENERIC_EXPERIMENT_CHOICE_DEFAULT, "", "" },
 125   { IDS_GENERIC_EXPERIMENT_CHOICE_ENABLED,
 126     switches::kEnableCompositingForFixedPosition, ""},
 127   { IDS_GENERIC_EXPERIMENT_CHOICE_DISABLED,
 128     switches::kDisableCompositingForFixedPosition, ""},
 129   { IDS_FLAGS_COMPOSITING_FOR_FIXED_POSITION_HIGH_DPI,
 130     switches::kEnableHighDpiCompositingForFixedPosition, ""}
 131 };
 132
 133 const Experiment::Choice kEnableCompositingForTransitionChoices[] = {
 134   { IDS_GENERIC_EXPERIMENT_CHOICE_DEFAULT, "", "" },
 135   { IDS_GENERIC_EXPERIMENT_CHOICE_ENABLED,
 136     switches::kEnableCompositingForTransition, ""},
 137   { IDS_GENERIC_EXPERIMENT_CHOICE_DISABLED,
 138     switches::kDisableCompositingForTransition, ""},
 139 };
 140
 141 const Experiment::Choice kEnableAcceleratedFixedRootBackgroundChoices[] = {
 142   { IDS_GENERIC_EXPERIMENT_CHOICE_DEFAULT, "", "" },
 143   { IDS_GENERIC_EXPERIMENT_CHOICE_ENABLED,
 144     switches::kEnableAcceleratedFixedRootBackground, ""},
 145   { IDS_GENERIC_EXPERIMENT_CHOICE_DISABLED,
 146     switches::kDisableAcceleratedFixedRootBackground, ""},
 147 };
 148
 149 const Experiment::Choice kGDIPresentChoices[] = {
 150   { IDS_GENERIC_EXPERIMENT_CHOICE_DEFAULT, "", "" },
 151   { IDS_FLAGS_PRESENT_WITH_GDI_FIRST_SHOW,
 152     switches::kDoFirstShowPresentWithGDI, ""},
 153   { IDS_FLAGS_PRESENT_WITH_GDI_ALL_SHOW,
 154     switches::kDoAllShowPresentWithGDI, ""}
 155 };
 156
 157 const Experiment::Choice kTouchEventsChoices[] = {
 158   { IDS_GENERIC_EXPERIMENT_CHOICE_AUTOMATIC, "", "" },
 159   { IDS_GENERIC_EXPERIMENT_CHOICE_ENABLED,
 160     switches::kTouchEvents,
 161     switches::kTouchEventsEnabled },
 162   { IDS_GENERIC_EXPERIMENT_CHOICE_DISABLED,
 163     switches::kTouchEvents,
 164     switches::kTouchEventsDisabled }
 165 };
 166
 167 const Experiment::Choice kTouchOptimizedUIChoices[] = {
 168   { IDS_GENERIC_EXPERIMENT_CHOICE_AUTOMATIC, "", "" },
 169   { IDS_GENERIC_EXPERIMENT_CHOICE_ENABLED,
 170     switches::kTouchOptimizedUI,
 171     switches::kTouchOptimizedUIEnabled },
 172   { IDS_GENERIC_EXPERIMENT_CHOICE_DISABLED,
 173     switches::kTouchOptimizedUI,
 174     switches::kTouchOptimizedUIDisabled }
 175 };
 176
 177 const Experiment::Choice kNaClDebugMaskChoices[] = {
 178   { IDS_GENERIC_EXPERIMENT_CHOICE_DEFAULT, "", "" },
 179   // Secure shell can be used on ChromeOS for forwarding the TCP port opened by
 180   // debug stub to a remote machine. Since secure shell uses NaCl, we provide
 181   // an option to switch off its debugging.
 182   { IDS_NACL_DEBUG_MASK_CHOICE_EXCLUDE_UTILS,
 183       switches::kNaClDebugMask, "!*://*/*ssh_client.nmf" },
 184   { IDS_NACL_DEBUG_MASK_CHOICE_INCLUDE_DEBUG,
 185       switches::kNaClDebugMask, "*://*/*debug.nmf" }
 186 };
 187
 188 #if defined(OS_CHROMEOS)
 189
 190 const Experiment::Choice kChromeCaptivePortalDetectionChoices[] = {
 191   { IDS_GENERIC_EXPERIMENT_CHOICE_DEFAULT, "", "" },
 192   { IDS_FLAGS_CHROME_CAPTIVE_PORTAL_DETECTOR,
 193     chromeos::switches::kEnableChromeCaptivePortalDetector, "" },
 194   { IDS_FLAGS_SHILL_CAPTIVE_PORTAL_DETECTOR,
 195     chromeos::switches::kDisableChromeCaptivePortalDetector, "" }
 196 };
 197
 198 #endif
 199
 200 const Experiment::Choice kImplSidePaintingChoices[] = {
 201   { IDS_GENERIC_EXPERIMENT_CHOICE_DEFAULT, "", "" },
 202   { IDS_GENERIC_EXPERIMENT_CHOICE_ENABLED,
 203     cc::switches::kEnableImplSidePainting, ""},
 204   { IDS_GENERIC_EXPERIMENT_CHOICE_DISABLED,
 205     cc::switches::kDisableImplSidePainting, ""}
 206 };
 207
 208 const Experiment::Choice kDelegatedRendererChoices[] = {
 209   { IDS_GENERIC_EXPERIMENT_CHOICE_DEFAULT, "", "" },
 210   { IDS_GENERIC_EXPERIMENT_CHOICE_ENABLED,
 211     switches::kEnableDelegatedRenderer, ""},
 212   { IDS_GENERIC_EXPERIMENT_CHOICE_DISABLED,
 213     switches::kDisableDelegatedRenderer, ""}
 214 };
 215
 216 const Experiment::Choice kMaxTilesForInterestAreaChoices[] = {
 217   { IDS_GENERIC_EXPERIMENT_CHOICE_DEFAULT, "", "" },
 218   { IDS_FLAGS_MAX_TILES_FOR_INTEREST_AREA_SHORT,
 219     cc::switches::kMaxTilesForInterestArea, "64"},
 220   { IDS_FLAGS_MAX_TILES_FOR_INTEREST_AREA_TALL,
 221     cc::switches::kMaxTilesForInterestArea, "128"},
 222   { IDS_FLAGS_MAX_TILES_FOR_INTEREST_AREA_GRANDE,
 223     cc::switches::kMaxTilesForInterestArea, "256"},
 224   { IDS_FLAGS_MAX_TILES_FOR_INTEREST_AREA_VENTI,
 225     cc::switches::kMaxTilesForInterestArea, "512"}
 226 };
 227
 228 const Experiment::Choice kDefaultTileWidthChoices[] = {
 229   { IDS_GENERIC_EXPERIMENT_CHOICE_DEFAULT, "", "" },
 230   { IDS_FLAGS_DEFAULT_TILE_WIDTH_SHORT,
 231     switches::kDefaultTileWidth, "128"},
 232   { IDS_FLAGS_DEFAULT_TILE_WIDTH_TALL,
 233     switches::kDefaultTileWidth, "256"},
 234   { IDS_FLAGS_DEFAULT_TILE_WIDTH_GRANDE,
 235     switches::kDefaultTileWidth, "512"},
 236   { IDS_FLAGS_DEFAULT_TILE_WIDTH_VENTI,
 237     switches::kDefaultTileWidth, "1024"}
 238 };
 239
 240 const Experiment::Choice kDefaultTileHeightChoices[] = {
 241   { IDS_GENERIC_EXPERIMENT_CHOICE_DEFAULT, "", "" },
 242   { IDS_FLAGS_DEFAULT_TILE_HEIGHT_SHORT,
 243     switches::kDefaultTileHeight, "128"},
 244   { IDS_FLAGS_DEFAULT_TILE_HEIGHT_TALL,
 245     switches::kDefaultTileHeight, "256"},
 246   { IDS_FLAGS_DEFAULT_TILE_HEIGHT_GRANDE,
 247     switches::kDefaultTileHeight, "512"},
 248   { IDS_FLAGS_DEFAULT_TILE_HEIGHT_VENTI,
 249     switches::kDefaultTileHeight, "1024"}
 250 };
 251
 252 const Experiment::Choice kSimpleCacheBackendChoices[] = {
 253   { IDS_GENERIC_EXPERIMENT_CHOICE_DEFAULT, "", "" },
 254   { IDS_GENERIC_EXPERIMENT_CHOICE_DISABLED,
 255     switches::kUseSimpleCacheBackend, "off" },
 256   { IDS_GENERIC_EXPERIMENT_CHOICE_ENABLED,
 257     switches::kUseSimpleCacheBackend, "on"}
 258 };
 259
 260 const Experiment::Choice kTabCaptureUpscaleQualityChoices[] = {
 261   { IDS_GENERIC_EXPERIMENT_CHOICE_DEFAULT, "", "" },
 262   { IDS_FLAGS_TAB_CAPTURE_SCALE_QUALITY_FAST,
 263     switches::kTabCaptureUpscaleQuality, "fast" },
 264   { IDS_FLAGS_TAB_CAPTURE_SCALE_QUALITY_GOOD,
 265     switches::kTabCaptureUpscaleQuality, "good" },
 266   { IDS_FLAGS_TAB_CAPTURE_SCALE_QUALITY_BEST,
 267     switches::kTabCaptureUpscaleQuality, "best" },
 268 };
 269
 270 const Experiment::Choice kTabCaptureDownscaleQualityChoices[] = {
 271   { IDS_GENERIC_EXPERIMENT_CHOICE_DEFAULT, "", "" },
 272   { IDS_FLAGS_TAB_CAPTURE_SCALE_QUALITY_FAST,
 273     switches::kTabCaptureDownscaleQuality, "fast" },
 274   { IDS_FLAGS_TAB_CAPTURE_SCALE_QUALITY_GOOD,
 275     switches::kTabCaptureDownscaleQuality, "good" },
 276   { IDS_FLAGS_TAB_CAPTURE_SCALE_QUALITY_BEST,
 277     switches::kTabCaptureDownscaleQuality, "best" },
 278 };
 279
 280 // RECORDING USER METRICS FOR FLAGS:
 281 // -----------------------------------------------------------------------------
 282 // The first line of the experiment is the internal name. If you'd like to
 283 // gather statistics about the usage of your flag, you should append a marker
 284 // comment to the end of the feature name, like so:
 285 //   "my-special-feature",  // FLAGS:RECORD_UMA
 286 //
 287 // After doing that, run //chrome/tools/extract_actions.py (see instructions at
 288 // the top of that file for details) to update the chromeactions.txt file, which
 289 // will enable UMA to record your feature flag.
 290 //
 291 // After your feature has shipped under a flag, you can locate the metrics under
 292 // the action name AboutFlags_internal-action-name. Actions are recorded once
 293 // per startup, so you should divide this number by AboutFlags_StartupTick to
 294 // get a sense of usage. Note that this will not be the same as number of users
 295 // with a given feature enabled because users can quit and relaunch the
 296 // application multiple times over a given time interval. The dashboard also
 297 // shows you how many (metrics reporting) users have enabled the flag over the
 298 // last seven days. However, note that this is not the same as the number of
 299 // users who have the flag enabled, since enabling the flag happens once,
 300 // whereas running with the flag enabled happens until the user flips the flag
 301 // again.
 302
 303 // To add a new experiment add to the end of kExperiments. There are two
 304 // distinct types of experiments:
 305 // . SINGLE_VALUE: experiment is either on or off. Use the SINGLE_VALUE_TYPE
 306 //   macro for this type supplying the command line to the macro.
 307 // . MULTI_VALUE: a list of choices, the first of which should correspond to a
 308 //   deactivated state for this lab (i.e. no command line option).  To specify
 309 //   this type of experiment use the macro MULTI_VALUE_TYPE supplying it the
 310 //   array of choices.
 311 // See the documentation of Experiment for details on the fields.
 312 //
 313 // When adding a new choice, add it to the end of the list.
 314 const Experiment kExperiments[] = {
 315   {
 316     "expose-for-tabs",  // FLAGS:RECORD_UMA
 317     IDS_FLAGS_TABPOSE_NAME,
 318     IDS_FLAGS_TABPOSE_DESCRIPTION,
 319     kOsMac,
 320 #if defined(OS_MACOSX)
 321     // The switch exists only on OS X.
 322     SINGLE_VALUE_TYPE(switches::kEnableExposeForTabs)
 323 #else
 324     SINGLE_VALUE_TYPE("")
 325 #endif
 326   },
 327   {
 328     "conflicting-modules-check",  // FLAGS:RECORD_UMA
 329     IDS_FLAGS_CONFLICTS_CHECK_NAME,
 330     IDS_FLAGS_CONFLICTS_CHECK_DESCRIPTION,
 331     kOsWin,
 332     SINGLE_VALUE_TYPE(switches::kConflictingModulesCheck)
 333   },
 334   {
 335     "ignore-gpu-blacklist",
 336     IDS_FLAGS_IGNORE_GPU_BLACKLIST_NAME,
 337     IDS_FLAGS_IGNORE_GPU_BLACKLIST_DESCRIPTION,
 338     kOsAll,
 339     SINGLE_VALUE_TYPE(switches::kIgnoreGpuBlacklist)
 340   },
 341   {
 342     "force-compositing-mode-2",
 343     IDS_FLAGS_FORCE_COMPOSITING_MODE_NAME,
 344     IDS_FLAGS_FORCE_COMPOSITING_MODE_DESCRIPTION,
 345     kOsMac | kOsWin | kOsLinux,
 346     ENABLE_DISABLE_VALUE_TYPE(switches::kForceCompositingMode,
 347                               switches::kDisableForceCompositingMode)
 348   },
 349   {
 350     "threaded-compositing-mode",
 351     IDS_FLAGS_THREADED_COMPOSITING_MODE_NAME,
 352     IDS_FLAGS_THREADED_COMPOSITING_MODE_DESCRIPTION,
 353     kOsMac | kOsWin | kOsLinux,
 354     ENABLE_DISABLE_VALUE_TYPE(switches::kEnableThreadedCompositing,
 355                               switches::kDisableThreadedCompositing)
 356   },
 357   {
 358     "force-accelerated-composited-scrolling",
 359      IDS_FLAGS_FORCE_ACCELERATED_OVERFLOW_SCROLL_MODE_NAME,
 360      IDS_FLAGS_FORCE_ACCELERATED_OVERFLOW_SCROLL_MODE_DESCRIPTION,
 361      kOsAll,
 362      ENABLE_DISABLE_VALUE_TYPE(switches::kEnableAcceleratedOverflowScroll,
 363                                switches::kDisableAcceleratedOverflowScroll)
 364   },
 365   {
 366     "present-with-GDI",
 367     IDS_FLAGS_PRESENT_WITH_GDI_NAME,
 368     IDS_FLAGS_PRESENT_WITH_GDI_DESCRIPTION,
 369     kOsWin,
 370     MULTI_VALUE_TYPE(kGDIPresentChoices)
 371   },
 372   {
 373     "enable-experimental-canvas-features",
 374     IDS_FLAGS_ENABLE_EXPERIMENTAL_CANVAS_FEATURES_NAME,
 375     IDS_FLAGS_ENABLE_EXPERIMENTAL_CANVAS_FEATURES_DESCRIPTION,
 376     kOsAll,
 377     SINGLE_VALUE_TYPE(switches::kEnableExperimentalCanvasFeatures)
 378   },
 379   {
 380     "disable-accelerated-2d-canvas",
 381     IDS_FLAGS_DISABLE_ACCELERATED_2D_CANVAS_NAME,
 382     IDS_FLAGS_DISABLE_ACCELERATED_2D_CANVAS_DESCRIPTION,
 383     kOsAll,
 384     SINGLE_VALUE_TYPE(switches::kDisableAccelerated2dCanvas)
 385   },
 386   {
 387     "disable-threaded-animation",
 388     IDS_FLAGS_DISABLE_THREADED_ANIMATION_NAME,
 389     IDS_FLAGS_DISABLE_THREADED_ANIMATION_DESCRIPTION,
 390     kOsAll,
 391     SINGLE_VALUE_TYPE(cc::switches::kDisableThreadedAnimation)
 392   },
 393   {
 394     "composited-layer-borders",
 395     IDS_FLAGS_COMPOSITED_LAYER_BORDERS,
 396     IDS_FLAGS_COMPOSITED_LAYER_BORDERS_DESCRIPTION,
 397     kOsAll,
 398     SINGLE_VALUE_TYPE(cc::switches::kShowCompositedLayerBorders)
 399   },
 400   {
 401     "show-fps-counter",
 402     IDS_FLAGS_SHOW_FPS_COUNTER,
 403     IDS_FLAGS_SHOW_FPS_COUNTER_DESCRIPTION,
 404     kOsAll,
 405     SINGLE_VALUE_TYPE(cc::switches::kShowFPSCounter)
 406   },
 407   {
 408     "accelerated-filters",
 409     IDS_FLAGS_ACCELERATED_FILTERS,
 410     IDS_FLAGS_ACCELERATED_FILTERS_DESCRIPTION,
 411     kOsAll,
 412     SINGLE_VALUE_TYPE(switches::kEnableAcceleratedFilters)
 413   },
 414   {
 415     "disable-gpu-vsync",
 416     IDS_FLAGS_DISABLE_GPU_VSYNC_NAME,
 417     IDS_FLAGS_DISABLE_GPU_VSYNC_DESCRIPTION,
 418     kOsDesktop,
 419     SINGLE_VALUE_TYPE(switches::kDisableGpuVsync)
 420   },
 421   {
 422     "disable-webgl",
 423     IDS_FLAGS_DISABLE_WEBGL_NAME,
 424     IDS_FLAGS_DISABLE_WEBGL_DESCRIPTION,
 425     kOsAll,
 426     SINGLE_VALUE_TYPE(switches::kDisableExperimentalWebGL)
 427   },
 428   {
 429     "disable-webrtc",
 430     IDS_FLAGS_DISABLE_WEBRTC_NAME,
 431     IDS_FLAGS_DISABLE_WEBRTC_DESCRIPTION,
 432     kOsAndroid,
 433 #if defined(OS_ANDROID)
 434     SINGLE_VALUE_TYPE(switches::kDisableWebRTC)
 435 #else
 436     SINGLE_VALUE_TYPE("")
 437 #endif
 438   },
 439 #if defined(ENABLE_WEBRTC)
 440   {
 441     "enable-sctp-data-channels",
 442     IDS_FLAGS_ENABLE_SCTP_DATA_CHANNELS_NAME,
 443     IDS_FLAGS_ENABLE_SCTP_DATA_CHANNELS_DESCRIPTION,
 444     kOsAll,
 445     SINGLE_VALUE_TYPE(switches::kEnableSCTPDataChannels)
 446   },
 447   {
 448     "disable-device-enumeration",
 449     IDS_FLAGS_DISABLE_DEVICE_ENUMERATION_NAME,
 450     IDS_FLAGS_DISABLE_DEVICE_ENUMERATION_DESCRIPTION,
 451     kOsAll,
 452     SINGLE_VALUE_TYPE(switches::kDisableDeviceEnumeration)
 453   },
 454 #endif
 455 #if defined(OS_ANDROID)
 456   {
 457     "disable-webaudio",
 458     IDS_FLAGS_DISABLE_WEBAUDIO_NAME,
 459     IDS_FLAGS_DISABLE_WEBAUDIO_DESCRIPTION,
 460     kOsAndroid,
 461     SINGLE_VALUE_TYPE(switches::kDisableWebAudio)
 462   },
 463 #endif
 464   {
 465     "fixed-position-creates-stacking-context",
 466     IDS_FLAGS_FIXED_POSITION_CREATES_STACKING_CONTEXT_NAME,
 467     IDS_FLAGS_FIXED_POSITION_CREATES_STACKING_CONTEXT_DESCRIPTION,
 468     kOsAll,
 469     ENABLE_DISABLE_VALUE_TYPE(
 470         switches::kEnableFixedPositionCreatesStackingContext,
 471         switches::kDisableFixedPositionCreatesStackingContext)
 472   },
 473   {
 474     "enable-compositing-for-fixed-position",
 475     IDS_FLAGS_COMPOSITING_FOR_FIXED_POSITION_NAME,
 476     IDS_FLAGS_COMPOSITING_FOR_FIXED_POSITION_DESCRIPTION,
 477     kOsAll,
 478     MULTI_VALUE_TYPE(kEnableCompositingForFixedPositionChoices)
 479   },
 480   {
 481     "enable-compositing-for-transition",
 482     IDS_FLAGS_COMPOSITING_FOR_TRANSITION_NAME,
 483     IDS_FLAGS_COMPOSITING_FOR_TRANSITION_DESCRIPTION,
 484     kOsAll,
 485     MULTI_VALUE_TYPE(kEnableCompositingForTransitionChoices)
 486   },
 487   {
 488     "enable-accelerated-fixed-root-background",
 489     IDS_FLAGS_ACCELERATED_FIXED_ROOT_BACKGROUND_NAME,
 490     IDS_FLAGS_ACCELERATED_FIXED_ROOT_BACKGROUND_DESCRIPTION,
 491     kOsAll,
 492     MULTI_VALUE_TYPE(kEnableAcceleratedFixedRootBackgroundChoices)
 493   },
 494   // TODO(bbudge): When NaCl is on by default, remove this flag entry.
 495   {
 496     "enable-nacl",  // FLAGS:RECORD_UMA
 497     IDS_FLAGS_ENABLE_NACL_NAME,
 498     IDS_FLAGS_ENABLE_NACL_DESCRIPTION,
 499     kOsDesktop,
 500     SINGLE_VALUE_TYPE(switches::kEnableNaCl)
 501   },
 502   {
 503     "enable-nacl-debug",  // FLAGS:RECORD_UMA
 504     IDS_FLAGS_ENABLE_NACL_DEBUG_NAME,
 505     IDS_FLAGS_ENABLE_NACL_DEBUG_DESCRIPTION,
 506     kOsDesktop,
 507     SINGLE_VALUE_TYPE(switches::kEnableNaClDebug)
 508   },
 509   {
 510     "nacl-debug-mask",  // FLAGS:RECORD_UMA
 511     IDS_FLAGS_NACL_DEBUG_MASK_NAME,
 512     IDS_FLAGS_NACL_DEBUG_MASK_DESCRIPTION,
 513     kOsDesktop,
 514     MULTI_VALUE_TYPE(kNaClDebugMaskChoices)
 515   },
 516   {
 517     "enable-pnacl",  // FLAGS:RECORD_UMA
 518     IDS_FLAGS_ENABLE_PNACL_NAME,
 519     IDS_FLAGS_ENABLE_PNACL_DESCRIPTION,
 520     kOsDesktop,
 521     SINGLE_VALUE_TYPE(switches::kEnablePnacl)
 522   },
 523   {
 524     "extension-apis",  // FLAGS:RECORD_UMA
 525     IDS_FLAGS_EXPERIMENTAL_EXTENSION_APIS_NAME,
 526     IDS_FLAGS_EXPERIMENTAL_EXTENSION_APIS_DESCRIPTION,
 527     kOsDesktop,
 528     SINGLE_VALUE_TYPE(extensions::switches::kEnableExperimentalExtensionApis)
 529   },
 530   {
 531     "extensions-on-chrome-urls",
 532     IDS_FLAGS_EXTENSIONS_ON_CHROME_URLS_NAME,
 533     IDS_FLAGS_EXTENSIONS_ON_CHROME_URLS_DESCRIPTION,
 534     kOsAll,
 535     SINGLE_VALUE_TYPE(extensions::switches::kExtensionsOnChromeURLs)
 536   },
 537   {
 538     "enable-fast-unload",
 539     IDS_FLAGS_ENABLE_FAST_UNLOAD_NAME,
 540     IDS_FLAGS_ENABLE_FAST_UNLOAD_DESCRIPTION,
 541     kOsAll,
 542     SINGLE_VALUE_TYPE(switches::kEnableFastUnload)
 543   },
 544   {
 545     "enable-adview",
 546     IDS_FLAGS_ENABLE_ADVIEW_NAME,
 547     IDS_FLAGS_ENABLE_ADVIEW_DESCRIPTION,
 548     kOsDesktop,
 549     SINGLE_VALUE_TYPE(switches::kEnableAdview)
 550   },
 551   {
 552     "enable-adview-src-attribute",
 553     IDS_FLAGS_ENABLE_ADVIEW_SRC_ATTRIBUTE_NAME,
 554     IDS_FLAGS_ENABLE_ADVIEW_SRC_ATTRIBUTE_DESCRIPTION,
 555     kOsDesktop,
 556     SINGLE_VALUE_TYPE(switches::kEnableAdviewSrcAttribute)
 557   },
 558   {
 559     "enable-app-window-controls",
 560     IDS_FLAGS_ENABLE_APP_WINDOW_CONTROLS_NAME,
 561     IDS_FLAGS_ENABLE_APP_WINDOW_CONTROLS_DESCRIPTION,
 562     kOsDesktop,
 563     SINGLE_VALUE_TYPE(switches::kEnableAppWindowControls)
 564   },
 565   {
 566     "script-badges",
 567     IDS_FLAGS_SCRIPT_BADGES_NAME,
 568     IDS_FLAGS_SCRIPT_BADGES_DESCRIPTION,
 569     kOsDesktop,
 570     SINGLE_VALUE_TYPE(switches::kScriptBadges)
 571   },
 572   {
 573     "script-bubble",
 574     IDS_FLAGS_SCRIPT_BUBBLE_NAME,
 575     IDS_FLAGS_SCRIPT_BUBBLE_DESCRIPTION,
 576     kOsDesktop,
 577     ENABLE_DISABLE_VALUE_TYPE_AND_VALUE(switches::kScriptBubble, "1",
 578                                         switches::kScriptBubble, "0")
 579   },
 580   {
 581     "apps-new-install-bubble",
 582     IDS_FLAGS_APPS_NEW_INSTALL_BUBBLE_NAME,
 583     IDS_FLAGS_APPS_NEW_INSTALL_BUBBLE_DESCRIPTION,
 584     kOsDesktop,
 585     SINGLE_VALUE_TYPE(switches::kAppsNewInstallBubble)
 586   },
 587   {
 588     "disable-hyperlink-auditing",
 589     IDS_FLAGS_DISABLE_HYPERLINK_AUDITING_NAME,
 590     IDS_FLAGS_DISABLE_HYPERLINK_AUDITING_DESCRIPTION,
 591     kOsAll,
 592     SINGLE_VALUE_TYPE(switches::kNoPings)
 593   },
 594   {
 595     "tab-groups-context-menu",
 596     IDS_FLAGS_TAB_GROUPS_CONTEXT_MENU_NAME,
 597     IDS_FLAGS_TAB_GROUPS_CONTEXT_MENU_DESCRIPTION,
 598     kOsWin,
 599     SINGLE_VALUE_TYPE(switches::kEnableTabGroupsContextMenu)
 600   },
 601   {
 602     "enable-instant-extended-api",
 603     IDS_FLAGS_ENABLE_INSTANT_EXTENDED_API,
 604     IDS_FLAGS_ENABLE_INSTANT_EXTENDED_API_DESCRIPTION,
 605     kOsMac | kOsWin | kOsCrOS,
 606     ENABLE_DISABLE_VALUE_TYPE(switches::kEnableInstantExtendedAPI,
 607                               switches::kDisableInstantExtendedAPI)
 608   },
 609   {
 610     "enable-local-first-load-ntp",
 611     IDS_FLAGS_ENABLE_LOCAL_FIRST_LOAD_NTP,
 612     IDS_FLAGS_ENABLE_LOCAL_FIRST_LOAD_NTP_DESCRIPTION,
 613     kOsMac | kOsWin | kOsCrOS,
 614     ENABLE_DISABLE_VALUE_TYPE(switches::kEnableLocalFirstLoadNTP,
 615                               switches::kDisableLocalFirstLoadNTP)
 616   },
 617 #if defined(OS_ANDROID)
 618   {
 619     "enable-new-ntp",
 620     IDS_FLAGS_ENABLE_NEW_NTP,
 621     IDS_FLAGS_ENABLE_NEW_NTP_DESCRIPTION,
 622     kOsAndroid,
 623     SINGLE_VALUE_TYPE(switches::kEnableNewNTP)
 624   },
 625 #endif
 626   {
 627     "static-ip-config",
 628     IDS_FLAGS_STATIC_IP_CONFIG_NAME,
 629     IDS_FLAGS_STATIC_IP_CONFIG_DESCRIPTION,
 630     kOsCrOS,
 631 #if defined(OS_CHROMEOS)
 632     // This switch exists only on Chrome OS.
 633     SINGLE_VALUE_TYPE(chromeos::switches::kEnableStaticIPConfig)
 634 #else
 635     SINGLE_VALUE_TYPE("")
 636 #endif
 637   },
 638   {
 639     "show-autofill-type-predictions",
 640     IDS_FLAGS_SHOW_AUTOFILL_TYPE_PREDICTIONS_NAME,
 641     IDS_FLAGS_SHOW_AUTOFILL_TYPE_PREDICTIONS_DESCRIPTION,
 642     kOsAll,
 643     SINGLE_VALUE_TYPE(autofill::switches::kShowAutofillTypePredictions)
 644   },
 645   {
 646     "enable-gesture-tap-highlight",
 647     IDS_FLAGS_ENABLE_GESTURE_TAP_HIGHLIGHTING_NAME,
 648     IDS_FLAGS_ENABLE_GESTURE_TAP_HIGHLIGHTING_DESCRIPTION,
 649     kOsLinux | kOsCrOS,
 650     ENABLE_DISABLE_VALUE_TYPE(switches::kEnableGestureTapHighlight,
 651                               switches::kDisableGestureTapHighlight)
 652   },
 653   {
 654     "enable-smooth-scrolling",  // FLAGS:RECORD_UMA
 655     IDS_FLAGS_ENABLE_SMOOTH_SCROLLING_NAME,
 656     IDS_FLAGS_ENABLE_SMOOTH_SCROLLING_DESCRIPTION,
 657     // Can't expose the switch unless the code is compiled in.
 658     // On by default for the Mac (different implementation in WebKit).
 659     kOsWin | kOsLinux,
 660     SINGLE_VALUE_TYPE(switches::kEnableSmoothScrolling)
 661   },
 662   {
 663     "enable-panels",
 664     IDS_FLAGS_ENABLE_PANELS_NAME,
 665     IDS_FLAGS_ENABLE_PANELS_DESCRIPTION,
 666     kOsDesktop,
 667     SINGLE_VALUE_TYPE(switches::kEnablePanels)
 668   },
 669   {
 670     // See http://crbug.com/120416 for how to remove this flag.
 671     "save-page-as-mhtml",  // FLAGS:RECORD_UMA
 672     IDS_FLAGS_SAVE_PAGE_AS_MHTML_NAME,
 673     IDS_FLAGS_SAVE_PAGE_AS_MHTML_DESCRIPTION,
 674     kOsMac | kOsWin | kOsLinux,
 675     SINGLE_VALUE_TYPE(switches::kSavePageAsMHTML)
 676   },
 677   {
 678     "enable-autologin",
 679     IDS_FLAGS_ENABLE_AUTOLOGIN_NAME,
 680     IDS_FLAGS_ENABLE_AUTOLOGIN_DESCRIPTION,
 681     kOsMac | kOsWin | kOsLinux,
 682     SINGLE_VALUE_TYPE(switches::kEnableAutologin)
 683   },
 684   {
 685     "enable-quic",
 686     IDS_FLAGS_ENABLE_QUIC_NAME,
 687     IDS_FLAGS_ENABLE_QUIC_DESCRIPTION,
 688     kOsAll,
 689     ENABLE_DISABLE_VALUE_TYPE(switches::kEnableQuic,
 690                               switches::kDisableQuic)
 691   },
 692   {
 693     "enable-quic-https",
 694     IDS_FLAGS_ENABLE_QUIC_HTTPS_NAME,
 695     IDS_FLAGS_ENABLE_QUIC_HTTPS_DESCRIPTION,
 696     kOsAll,
 697     ENABLE_DISABLE_VALUE_TYPE(switches::kEnableQuicHttps,
 698                               switches::kDisableQuicHttps)
 699   },
 700   {
 701     "enable-spdy4a2",
 702     IDS_FLAGS_ENABLE_SPDY4A2_NAME,
 703     IDS_FLAGS_ENABLE_SPDY4A2_DESCRIPTION,
 704     kOsAll,
 705     SINGLE_VALUE_TYPE(switches::kEnableSpdy4a2)
 706   },
 707   {
 708     "enable-http2-draft-04",
 709     IDS_FLAGS_ENABLE_HTTP2_DRAFT_04_NAME,
 710     IDS_FLAGS_ENABLE_HTTP2_DRAFT_04_DESCRIPTION,
 711     kOsAll,
 712     SINGLE_VALUE_TYPE(switches::kEnableHttp2Draft04)
 713   },
 714   {
 715     "enable-async-dns",
 716     IDS_FLAGS_ENABLE_ASYNC_DNS_NAME,
 717     IDS_FLAGS_ENABLE_ASYNC_DNS_DESCRIPTION,
 718     kOsWin | kOsMac | kOsLinux | kOsCrOS,
 719     ENABLE_DISABLE_VALUE_TYPE(switches::kEnableAsyncDns,
 720                               switches::kDisableAsyncDns)
 721   },
 722   {
 723     "disable-media-source",
 724     IDS_FLAGS_DISABLE_WEBKIT_MEDIA_SOURCE_NAME,
 725     IDS_FLAGS_DISABLE_WEBKIT_MEDIA_SOURCE_DESCRIPTION,
 726     kOsAll,
 727     SINGLE_VALUE_TYPE(switches::kDisableWebKitMediaSource)
 728   },
 729   {
 730     "enable-encrypted-media",
 731     IDS_FLAGS_ENABLE_ENCRYPTED_MEDIA_NAME,
 732     IDS_FLAGS_ENABLE_ENCRYPTED_MEDIA_DESCRIPTION,
 733     kOsAll,
 734     SINGLE_VALUE_TYPE(switches::kEnableEncryptedMedia)
 735   },
 736   {
 737     "disable-encrypted-media",
 738     IDS_FLAGS_DISABLE_PREFIXED_ENCRYPTED_MEDIA_NAME,
 739     IDS_FLAGS_DISABLE_PREFIXED_ENCRYPTED_MEDIA_DESCRIPTION,
 740     kOsAll,
 741     SINGLE_VALUE_TYPE(switches::kDisableLegacyEncryptedMedia)
 742   },
 743   {
 744     "override-encrypted-media-canplaytype",
 745     IDS_FLAGS_ENCRYPTED_MEDIA_CANPLAYTYPE_OVERRIDE_NAME,
 746     IDS_FLAGS_ENCRYPTED_MEDIA_CANPLAYTYPE_OVERRIDE_DESCRIPTION,
 747     kOsMac | kOsWin,
 748     SINGLE_VALUE_TYPE(switches::kOverrideEncryptedMediaCanPlayType)
 749   },
 750   {
 751     "enable-opus-playback",
 752     IDS_FLAGS_ENABLE_OPUS_PLAYBACK_NAME,
 753     IDS_FLAGS_ENABLE_OPUS_PLAYBACK_DESCRIPTION,
 754     kOsDesktop,
 755     SINGLE_VALUE_TYPE(switches::kEnableOpusPlayback)
 756   },
 757  {
 758     "enable-vp8-alpha-playback",
 759     IDS_FLAGS_ENABLE_VP8_ALPHA_PLAYBACK_NAME,
 760     IDS_FLAGS_ENABLE_VP8_ALPHA_PLAYBACK_DESCRIPTION,
 761     kOsDesktop,
 762     SINGLE_VALUE_TYPE(switches::kEnableVp8AlphaPlayback)
 763   },
 764   {
 765     "enable-managed-users",
 766     IDS_FLAGS_ENABLE_LOCALLY_MANAGED_USERS_NAME,
 767     IDS_FLAGS_ENABLE_LOCALLY_MANAGED_USERS_DESCRIPTION,
 768     kOsMac | kOsWin | kOsLinux | kOsCrOSOwnerOnly,
 769     SINGLE_VALUE_TYPE(switches::kEnableManagedUsers)
 770   },
 771 #if defined(USE_ASH)
 772   {
 773     "ash-disable-auto-maximizing",
 774     IDS_FLAGS_ASH_AUTO_MAXIMIZING_NAME,
 775     IDS_FLAGS_ASH_AUTO_MAXIMIZING_DESCRIPTION,
 776     kOsWin | kOsLinux | kOsCrOS,
 777     SINGLE_VALUE_TYPE(ash::switches::kAshDisableAutoMaximizing)
 778   },
 779   {
 780     "ash-disable-auto-window-placement",
 781     IDS_FLAGS_ASH_AUTO_WINDOW_PLACEMENT_NAME,
 782     IDS_FLAGS_ASH_AUTO_WINDOW_PLACEMENT_DESCRIPTION,
 783     kOsWin | kOsLinux | kOsCrOS,
 784     SINGLE_VALUE_TYPE(ash::switches::kAshDisableAutoWindowPlacement)
 785   },
 786   {
 787     "ash-disable-per-app-launcher",
 788     IDS_FLAGS_ASH_DISABLE_PER_APP_LAUNCHER_NAME,
 789     IDS_FLAGS_ASH_DISABLE_PER_APP_LAUNCHER_DESCRIPTION,
 790     kOsWin | kOsLinux | kOsCrOS,
 791     SINGLE_VALUE_TYPE(ash::switches::kAshDisablePerAppLauncher)
 792   },
 793 #endif
 794   {
 795     "per-tile-painting",
 796     IDS_FLAGS_PER_TILE_PAINTING_NAME,
 797     IDS_FLAGS_PER_TILE_PAINTING_DESCRIPTION,
 798     kOsMac | kOsLinux | kOsCrOS,
 799     SINGLE_VALUE_TYPE(cc::switches::kEnablePerTilePainting)
 800   },
 801   {
 802     "enable-javascript-harmony",
 803     IDS_FLAGS_ENABLE_JAVASCRIPT_HARMONY_NAME,
 804     IDS_FLAGS_ENABLE_JAVASCRIPT_HARMONY_DESCRIPTION,
 805     kOsAll,
 806     SINGLE_VALUE_TYPE_AND_VALUE(switches::kJavaScriptFlags, "--harmony")
 807   },
 808   {
 809     "enable-tab-browser-dragging",
 810     IDS_FLAGS_ENABLE_TAB_BROWSER_DRAGGING_NAME,
 811     IDS_FLAGS_ENABLE_TAB_BROWSER_DRAGGING_DESCRIPTION,
 812     kOsWin,
 813     SINGLE_VALUE_TYPE(switches::kTabBrowserDragging)
 814   },
 815   {
 816     "disable-restore-session-state",
 817     IDS_FLAGS_DISABLE_RESTORE_SESSION_STATE_NAME,
 818     IDS_FLAGS_DISABLE_RESTORE_SESSION_STATE_DESCRIPTION,
 819     kOsAll,
 820     SINGLE_VALUE_TYPE(switches::kDisableRestoreSessionState)
 821   },
 822   {
 823     "disable-software-rasterizer",
 824     IDS_FLAGS_DISABLE_SOFTWARE_RASTERIZER_NAME,
 825     IDS_FLAGS_DISABLE_SOFTWARE_RASTERIZER_DESCRIPTION,
 826 #if defined(ENABLE_SWIFTSHADER)
 827     kOsAll,
 828 #else
 829     0,
 830 #endif
 831     SINGLE_VALUE_TYPE(switches::kDisableSoftwareRasterizer)
 832   },
 833   {
 834     "enable-experimental-web-platform-features",
 835     IDS_FLAGS_EXPERIMENTAL_WEB_PLATFORM_FEATURES_NAME,
 836     IDS_FLAGS_EXPERIMENTAL_WEB_PLATFORM_FEATURES_DESCRIPTION,
 837     kOsAll,
 838     SINGLE_VALUE_TYPE(switches::kEnableExperimentalWebPlatformFeatures)
 839   },
 840   {
 841     "enable-css-shaders",
 842     IDS_FLAGS_CSS_SHADERS_NAME,
 843     IDS_FLAGS_CSS_SHADERS_DESCRIPTION,
 844     kOsAll,
 845     SINGLE_VALUE_TYPE(switches::kEnableCssShaders)
 846   },
 847   {
 848     "disable-ntp-other-sessions-menu",
 849     IDS_FLAGS_NTP_OTHER_SESSIONS_MENU_NAME,
 850     IDS_FLAGS_NTP_OTHER_SESSIONS_MENU_DESCRIPTION,
 851     kOsDesktop,
 852     SINGLE_VALUE_TYPE(switches::kDisableNTPOtherSessionsMenu)
 853   },
 854 #if defined(USE_ASH)
 855   {
 856     "enable-ash-oak",
 857     IDS_FLAGS_ENABLE_ASH_OAK_NAME,
 858     IDS_FLAGS_ENABLE_ASH_OAK_DESCRIPTION,
 859     kOsAll,
 860     SINGLE_VALUE_TYPE(ash::switches::kAshEnableOak),
 861   },
 862 #endif
 863   {
 864     "enable-devtools-experiments",
 865     IDS_FLAGS_ENABLE_DEVTOOLS_EXPERIMENTS_NAME,
 866     IDS_FLAGS_ENABLE_DEVTOOLS_EXPERIMENTS_DESCRIPTION,
 867     kOsDesktop,
 868     SINGLE_VALUE_TYPE(switches::kEnableDevToolsExperiments)
 869   },
 870   {
 871     "remote-debugging-raw-usb",
 872     IDS_FLAGS_REMOTE_DEBUGGING_RAW_USB_NAME,
 873     IDS_FLAGS_REMOTE_DEBUGGING_RAW_USB_DESCRIPTION,
 874     kOsDesktop,
 875     SINGLE_VALUE_TYPE(switches::kRemoteDebuggingRawUSB)
 876   },
 877   {
 878     "silent-debugger-extension-api",
 879     IDS_FLAGS_SILENT_DEBUGGER_EXTENSION_API_NAME,
 880     IDS_FLAGS_SILENT_DEBUGGER_EXTENSION_API_DESCRIPTION,
 881     kOsDesktop,
 882     SINGLE_VALUE_TYPE(switches::kSilentDebuggerExtensionAPI)
 883   },
 884   {
 885     "enable-suggestions-ntp",
 886     IDS_FLAGS_NTP_SUGGESTIONS_PAGE_NAME,
 887     IDS_FLAGS_NTP_SUGGESTIONS_PAGE_DESCRIPTION,
 888     kOsDesktop,
 889     SINGLE_VALUE_TYPE(switches::kEnableSuggestionsTabPage)
 890   },
 891   {
 892     "spellcheck-autocorrect",
 893     IDS_FLAGS_SPELLCHECK_AUTOCORRECT,
 894     IDS_FLAGS_SPELLCHECK_AUTOCORRECT_DESCRIPTION,
 895     kOsWin | kOsLinux | kOsCrOS,
 896     SINGLE_VALUE_TYPE(switches::kEnableSpellingAutoCorrect)
 897   },
 898   {
 899     "enable-scroll-prediction",
 900     IDS_FLAGS_ENABLE_SCROLL_PREDICTION_NAME,
 901     IDS_FLAGS_ENABLE_SCROLL_PREDICTION_DESCRIPTION,
 902     kOsDesktop,
 903     SINGLE_VALUE_TYPE(switches::kEnableScrollPrediction)
 904   },
 905   {
 906     "touch-events",
 907     IDS_TOUCH_EVENTS_NAME,
 908     IDS_TOUCH_EVENTS_DESCRIPTION,
 909     kOsDesktop,
 910     MULTI_VALUE_TYPE(kTouchEventsChoices)
 911   },
 912   {
 913     "touch-optimized-ui",
 914     IDS_FLAGS_TOUCH_OPTIMIZED_UI_NAME,
 915     IDS_FLAGS_TOUCH_OPTIMIZED_UI_DESCRIPTION,
 916     kOsWin,
 917     MULTI_VALUE_TYPE(kTouchOptimizedUIChoices)
 918   },
 919   {
 920     "disable-touch-adjustment",
 921     IDS_DISABLE_TOUCH_ADJUSTMENT_NAME,
 922     IDS_DISABLE_TOUCH_ADJUSTMENT_DESCRIPTION,
 923     kOsWin | kOsLinux | kOsCrOS,
 924     SINGLE_VALUE_TYPE(switches::kDisableTouchAdjustment)
 925   },
 926 #if defined(OS_CHROMEOS)
 927   {
 928       "ash-use-alternate-shelf",
 929       IDS_FLAGS_ALTERNATE_SHELF_LAYOUT_NAME,
 930       IDS_FLAGS_ALTERNATE_SHELF_LAYOUT_DESCRIPTION,
 931       kOsCrOS,
 932       SINGLE_VALUE_TYPE(ash::switches::kAshUseAlternateShelfLayout)
 933   },
 934   {
 935     "enable-background-loader",
 936     IDS_ENABLE_BACKLOADER_NAME,
 937     IDS_ENABLE_BACKLOADER_DESCRIPTION,
 938     kOsCrOS,
 939     SINGLE_VALUE_TYPE(chromeos::switches::kEnableBackgroundLoader)
 940   },
 941   {
 942     "enable-screensaver-extension",
 943     IDS_ENABLE_SCREENSAVER_EXTENSION_NAME,
 944     IDS_ENABLE_SCREENSAVER_EXTENSION_DESCRIPTION,
 945     kOsCrOS,
 946     SINGLE_VALUE_TYPE(chromeos::switches::kEnableScreensaverExtensions)
 947   },
 948   {
 949     "no-discard-tabs",
 950     IDS_FLAGS_NO_DISCARD_TABS_NAME,
 951     IDS_FLAGS_NO_DISCARD_TABS_DESCRIPTION,
 952     kOsCrOS,
 953     SINGLE_VALUE_TYPE(chromeos::switches::kNoDiscardTabs)
 954   },
 955   {
 956     "ash-enable-docked-windows",
 957     IDS_FLAGS_DOCKED_WINDOWS_NAME,
 958     IDS_FLAGS_DOCKED_WINDOWS_DESCRIPTION,
 959     kOsCrOS,
 960     SINGLE_VALUE_TYPE(ash::switches::kAshEnableDockedWindows)
 961   },
 962 #endif
 963   {
 964     "enable-download-resumption",
 965     IDS_FLAGS_ENABLE_DOWNLOAD_RESUMPTION_NAME,
 966     IDS_FLAGS_ENABLE_DOWNLOAD_RESUMPTION_DESCRIPTION,
 967     kOsDesktop,
 968     SINGLE_VALUE_TYPE(switches::kEnableDownloadResumption)
 969   },
 970   {
 971     "allow-nacl-socket-api",
 972     IDS_FLAGS_ALLOW_NACL_SOCKET_API_NAME,
 973     IDS_FLAGS_ALLOW_NACL_SOCKET_API_DESCRIPTION,
 974     kOsDesktop,
 975     SINGLE_VALUE_TYPE_AND_VALUE(switches::kAllowNaClSocketAPI, "*")
 976   },
 977   {
 978     "stacked-tab-strip",
 979     IDS_FLAGS_STACKED_TAB_STRIP_NAME,
 980     IDS_FLAGS_STACKED_TAB_STRIP_DESCRIPTION,
 981     kOsWin,
 982     SINGLE_VALUE_TYPE(switches::kEnableStackedTabStrip)
 983   },
 984   {
 985     "force-device-scale-factor",
 986     IDS_FLAGS_FORCE_HIGH_DPI_NAME,
 987     IDS_FLAGS_FORCE_HIGH_DPI_DESCRIPTION,
 988     kOsCrOS,
 989     SINGLE_VALUE_TYPE_AND_VALUE(switches::kForceDeviceScaleFactor, "2")
 990   },
 991 #if defined(OS_CHROMEOS)
 992   {
 993     "allow-touchpad-three-finger-click",
 994     IDS_FLAGS_ALLOW_TOUCHPAD_THREE_FINGER_CLICK_NAME,
 995     IDS_FLAGS_ALLOW_TOUCHPAD_THREE_FINGER_CLICK_DESCRIPTION,
 996     kOsCrOS,
 997     SINGLE_VALUE_TYPE(chromeos::switches::kEnableTouchpadThreeFingerClick)
 998   },
 999 #endif
1000 #if defined(USE_ASH)
1001   {
1002     "show-launcher-alignment-menu",
1003     IDS_FLAGS_SHOW_SHELF_ALIGNMENT_MENU_NAME,
1004     IDS_FLAGS_SHOW_SHELF_ALIGNMENT_MENU_DESCRIPTION,
1005     kOsAll,
1006     ENABLE_DISABLE_VALUE_TYPE(
1007         ash::switches::kShowShelfAlignmentMenu,
1008         ash::switches::kHideShelfAlignmentMenu)
1009   },
1010   {
1011     "disable-minimize-on-second-launcher-item-click",
1012     IDS_FLAGS_DISABLE_MINIMIZE_ON_SECOND_LAUNCHER_ITEM_CLICK_NAME,
1013     IDS_FLAGS_DISABLE_MINIMIZE_ON_SECOND_LAUNCHER_ITEM_CLICK_DESCRIPTION,
1014     kOsAll,
1015     SINGLE_VALUE_TYPE(switches::kDisableMinimizeOnSecondLauncherItemClick)
1016   },
1017   {
1018     "enable-overview-mode",
1019     IDS_FLAGS_OVERVIEW_MODE_NAME,
1020     IDS_FLAGS_OVERVIEW_MODE_DESCRIPTION,
1021     kOsCrOS,
1022     SINGLE_VALUE_TYPE(ash::switches::kAshEnableOverviewMode)
1023   },
1024   {
1025     "show-touch-hud",
1026     IDS_FLAGS_SHOW_TOUCH_HUD_NAME,
1027     IDS_FLAGS_SHOW_TOUCH_HUD_DESCRIPTION,
1028     kOsAll,
1029     SINGLE_VALUE_TYPE(ash::switches::kAshTouchHud)
1030   },
1031   {
1032     "enable-pinch",
1033     IDS_FLAGS_ENABLE_PINCH_SCALE_NAME,
1034     IDS_FLAGS_ENABLE_PINCH_SCALE_DESCRIPTION,
1035     kOsLinux | kOsWin | kOsCrOS,
1036     ENABLE_DISABLE_VALUE_TYPE(switches::kEnablePinch, switches::kDisablePinch),
1037   },
1038   {
1039     "enable-pinch-virtual-viewport",
1040     IDS_FLAGS_ENABLE_PINCH_VIRTUAL_VIEWPORT_NAME,
1041     IDS_FLAGS_ENABLE_PINCH_VIRTUAL_VIEWPORT_DESCRIPTION,
1042     kOsLinux | kOsWin | kOsCrOS,
1043     SINGLE_VALUE_TYPE(cc::switches::kEnablePinchVirtualViewport),
1044   },
1045   {
1046     "forced-maximize-mode",
1047     IDS_FLAGS_FORCE_MAXIMIZE_MODE_NAME,
1048     IDS_FLAGS_FORCE_MAXIMIZE_MODE_DESCRIPTION,
1049     kOsLinux | kOsWin | kOsCrOS,
1050     SINGLE_VALUE_TYPE(ash::switches::kForcedMaximizeMode),
1051   },
1052 #endif  // defined(USE_ASH)
1053 #if defined(OS_CHROMEOS)
1054   {
1055     "disable-boot-animation",
1056     IDS_FLAGS_DISABLE_BOOT_ANIMATION,
1057     IDS_FLAGS_DISABLE_BOOT_ANIMATION_DESCRIPTION,
1058     kOsCrOSOwnerOnly,
1059     SINGLE_VALUE_TYPE(chromeos::switches::kDisableBootAnimation),
1060   },
1061   {
1062     "captive-portal-detector",
1063     IDS_FLAGS_CAPTIVE_PORTAL_DETECTOR_NAME,
1064     IDS_FLAGS_CAPTIVE_PORTAL_DETECTOR_DESCRIPTION,
1065     kOsCrOSOwnerOnly,
1066     MULTI_VALUE_TYPE(kChromeCaptivePortalDetectionChoices),
1067   },
1068   {
1069     "disable-new-lock-animations",
1070     IDS_FLAGS_ASH_NEW_LOCK_ANIMATIONS,
1071     IDS_FLAGS_ASH_NEW_LOCK_ANIMATIONS_DESCRIPTION,
1072     kOsCrOS,
1073     SINGLE_VALUE_TYPE(ash::switches::kAshDisableNewLockAnimations),
1074   },
1075   {
1076     "file-manager-show-checkboxes",
1077     IDS_FLAGS_FILE_MANAGER_SHOW_CHECKBOXES_NAME,
1078     IDS_FLAGS_FILE_MANAGER_SHOW_CHECKBOXES_DESCRIPTION,
1079     kOsCrOS,
1080     SINGLE_VALUE_TYPE(chromeos::switches::kFileManagerShowCheckboxes)
1081   },
1082   {
1083     "file-manager-enable-webstore-integration",
1084     IDS_FLAGS_FILE_MANAGER_ENABLE_WEBSTORE_INTEGRATION,
1085     IDS_FLAGS_FILE_MANAGER_ENABLE_WEBSTORE_INTEGRATION_DESCRIPTION,
1086     kOsCrOS,
1087     SINGLE_VALUE_TYPE(chromeos::switches::kFileManagerEnableWebstoreIntegration)
1088   },
1089   {
1090     "disable-quickoffice-component-app",
1091     IDS_FLAGS_DISABLE_QUICKOFFICE_COMPONENT_APP_NAME,
1092     IDS_FLAGS_DISABLE_QUICKOFFICE_COMPONENT_APP_DESCRIPTION,
1093     kOsCrOS,
1094     SINGLE_VALUE_TYPE(chromeos::switches::kDisableQuickofficeComponentApp),
1095   },
1096 #endif  // defined(OS_CHROMEOS)
1097   {
1098     "views-textfield",
1099     IDS_FLAGS_VIEWS_TEXTFIELD_NAME,
1100     IDS_FLAGS_VIEWS_TEXTFIELD_DESCRIPTION,
1101     kOsWin,
1102     ENABLE_DISABLE_VALUE_TYPE(switches::kEnableViewsTextfield,
1103                               switches::kDisableViewsTextfield),
1104   },
1105   {
1106     "new-dialog-style",
1107     IDS_FLAGS_NEW_DIALOG_STYLE_NAME,
1108     IDS_FLAGS_NEW_DIALOG_STYLE_DESCRIPTION,
1109     kOsWin | kOsCrOS,
1110     ENABLE_DISABLE_VALUE_TYPE(switches::kEnableNewDialogStyle,
1111                               switches::kDisableNewDialogStyle),
1112   },
1113   { "disable-accelerated-video-decode",
1114     IDS_FLAGS_DISABLE_ACCELERATED_VIDEO_DECODE_NAME,
1115     IDS_FLAGS_DISABLE_ACCELERATED_VIDEO_DECODE_DESCRIPTION,
1116     kOsWin | kOsCrOS,
1117     SINGLE_VALUE_TYPE(switches::kDisableAcceleratedVideoDecode),
1118   },
1119 #if defined(USE_ASH)
1120   {
1121     "ash-debug-shortcuts",
1122     IDS_FLAGS_DEBUG_SHORTCUTS_NAME,
1123     IDS_FLAGS_DEBUG_SHORTCUTS_DESCRIPTION,
1124     kOsAll,
1125     SINGLE_VALUE_TYPE(ash::switches::kAshDebugShortcuts),
1126   },
1127 #endif
1128   {
1129     "enable-contacts",
1130     IDS_FLAGS_ENABLE_CONTACTS_NAME,
1131     IDS_FLAGS_ENABLE_CONTACTS_DESCRIPTION,
1132     kOsCrOS,
1133     SINGLE_VALUE_TYPE(switches::kEnableContacts)
1134   },
1135 #if defined(USE_ASH)
1136   { "ash-enable-advanced-gestures",
1137     IDS_FLAGS_ENABLE_ADVANCED_GESTURES_NAME,
1138     IDS_FLAGS_ENABLE_ADVANCED_GESTURES_DESCRIPTION,
1139     kOsCrOS,
1140     SINGLE_VALUE_TYPE(ash::switches::kAshEnableAdvancedGestures),
1141   },
1142   { "ash-disable-tab-scrubbing",
1143     IDS_FLAGS_DISABLE_TAB_SCRUBBING_NAME,
1144     IDS_FLAGS_DISABLE_TAB_SCRUBBING_DESCRIPTION,
1145     kOsCrOS,
1146     SINGLE_VALUE_TYPE(switches::kAshDisableTabScrubbing),
1147   },
1148   { "ash-disable-drag-and-drop-applist-to-launcher",
1149     IDS_FLAGS_DND_APPLIST_TO_LAUNCHER_NAME,
1150     IDS_FLAGS_DND_APPLIST_TO_LAUNCHER_DESCRIPTION,
1151     kOsCrOS,
1152     SINGLE_VALUE_TYPE(ash::switches::kAshDisableDragAndDropAppListToLauncher),
1153   },
1154   { "ash-immersive-fullscreen-2",
1155     IDS_FLAGS_ASH_IMMERSIVE_FULLSCREEN_NAME,
1156     IDS_FLAGS_ASH_IMMERSIVE_FULLSCREEN_DESCRIPTION,
1157     kOsCrOS,
1158     ENABLE_DISABLE_VALUE_TYPE(ash::switches::kAshEnableImmersiveFullscreen,
1159                               ash::switches::kAshDisableImmersiveFullscreen),
1160   },
1161 #if defined(OS_LINUX)
1162   { "ash-enable-memory-monitor",
1163       IDS_FLAGS_ENABLE_MEMORY_MONITOR_NAME,
1164       IDS_FLAGS_ENABLE_MEMORY_MONITOR_DESCRIPTION,
1165       kOsCrOS,
1166       SINGLE_VALUE_TYPE(ash::switches::kAshEnableMemoryMonitor),
1167   },
1168 #endif
1169 #endif
1170 #if defined(OS_CHROMEOS)
1171   { "use-new-network-configuration-handlers",
1172     IDS_FLAGS_CHROMEOS_USE_NEW_NETWORK_CONFIGURATION_HANDLERS_NAME,
1173     IDS_FLAGS_CHROMEOS_USE_NEW_NETWORK_CONFIGURATION_HANDLERS_DESCRIPTION,
1174     kOsCrOS,
1175     SINGLE_VALUE_TYPE(chromeos::switches::kUseNewNetworkConfigurationHandlers),
1176   },
1177   {
1178     "ash-audio-device-menu",
1179     IDS_FLAGS_ASH_AUDIO_DEVICE_MENU_NAME,
1180     IDS_FLAGS_ASH_AUDIO_DEVICE_MENU_DESCRIPTION,
1181     kOsCrOS,
1182     ENABLE_DISABLE_VALUE_TYPE(ash::switches::kAshEnableAudioDeviceMenu,
1183                               ash::switches::kAshDisableAudioDeviceMenu)
1184   },
1185   {
1186     "enable-carrier-switching",
1187     IDS_FLAGS_ENABLE_CARRIER_SWITCHING,
1188     IDS_FLAGS_ENABLE_CARRIER_SWITCHING_DESCRIPTION,
1189     kOsCrOS,
1190     SINGLE_VALUE_TYPE(chromeos::switches::kEnableCarrierSwitching)
1191   },
1192   {
1193     "enable-request-tablet-site",
1194     IDS_FLAGS_ENABLE_REQUEST_TABLET_SITE_NAME,
1195     IDS_FLAGS_ENABLE_REQUEST_TABLET_SITE_DESCRIPTION,
1196     kOsCrOS,
1197     SINGLE_VALUE_TYPE(chromeos::switches::kEnableRequestTabletSite)
1198   },
1199 #endif
1200   {
1201     "debug-packed-apps",
1202     IDS_FLAGS_DEBUG_PACKED_APP_NAME,
1203     IDS_FLAGS_DEBUG_PACKED_APP_DESCRIPTION,
1204     kOsDesktop,
1205     SINGLE_VALUE_TYPE(switches::kDebugPackedApps)
1206   },
1207   {
1208     "enable-password-generation",
1209     IDS_FLAGS_ENABLE_PASSWORD_GENERATION_NAME,
1210     IDS_FLAGS_ENABLE_PASSWORD_GENERATION_DESCRIPTION,
1211     kOsDesktop,
1212     SINGLE_VALUE_TYPE(switches::kEnablePasswordGeneration)
1213   },
1214   {
1215     "password-autofill-public-suffix-domain-matching",
1216     IDS_FLAGS_PASSWORD_AUTOFILL_PUBLIC_SUFFIX_DOMAIN_MATCHING_NAME,
1217     IDS_FLAGS_PASSWORD_AUTOFILL_PUBLIC_SUFFIX_DOMAIN_MATCHING_DESCRIPTION,
1218     kOsAndroid,
1219     ENABLE_DISABLE_VALUE_TYPE(
1220         switches::kEnablePasswordAutofillPublicSuffixDomainMatching,
1221         switches::kDisablePasswordAutofillPublicSuffixDomainMatching)
1222   },
1223   {
1224     "enable-deferred-image-decoding",
1225     IDS_FLAGS_ENABLE_DEFERRED_IMAGE_DECODING_NAME,
1226     IDS_FLAGS_ENABLE_DEFERRED_IMAGE_DECODING_DESCRIPTION,
1227     kOsMac | kOsLinux | kOsCrOS,
1228     SINGLE_VALUE_TYPE(switches::kEnableDeferredImageDecoding)
1229   },
1230   {
1231     "performance-monitor-gathering",
1232     IDS_FLAGS_PERFORMANCE_MONITOR_GATHERING_NAME,
1233     IDS_FLAGS_PERFORMANCE_MONITOR_GATHERING_DESCRIPTION,
1234     kOsAll,
1235     SINGLE_VALUE_TYPE(switches::kPerformanceMonitorGathering)
1236   },
1237   {
1238     "enable-experimental-form-filling",
1239     IDS_FLAGS_ENABLE_EXPERIMENTAL_FORM_FILLING_NAME,
1240     IDS_FLAGS_ENABLE_EXPERIMENTAL_FORM_FILLING_DESCRIPTION,
1241     kOsWin | kOsCrOS,
1242     SINGLE_VALUE_TYPE(autofill::switches::kEnableExperimentalFormFilling)
1243   },
1244   {
1245     "wallet-service-use-prod",
1246     IDS_FLAGS_ENABLE_WALLET_PRODUCTION_SERVICE_NAME,
1247     IDS_FLAGS_ENABLE_WALLET_PRODUCTION_SERVICE_DESCRIPTION,
1248     kOsCrOS | kOsWin,
1249     SINGLE_VALUE_TYPE(autofill::switches::kWalletServiceUseProd)
1250   },
1251   {
1252     "enable-interactive-autocomplete",
1253     IDS_FLAGS_ENABLE_INTERACTIVE_AUTOCOMPLETE_NAME,
1254     IDS_FLAGS_ENABLE_INTERACTIVE_AUTOCOMPLETE_DESCRIPTION,
1255     kOsWin | kOsCrOS | kOsAndroid | kOsMac,
1256     ENABLE_DISABLE_VALUE_TYPE(
1257         autofill::switches::kEnableInteractiveAutocomplete,
1258         autofill::switches::kDisableInteractiveAutocomplete)
1259   },
1260 #if defined(USE_AURA)
1261   {
1262     "overscroll-history-navigation",
1263     IDS_FLAGS_OVERSCROLL_HISTORY_NAVIGATION_NAME,
1264     IDS_FLAGS_OVERSCROLL_HISTORY_NAVIGATION_DESCRIPTION,
1265     kOsAll,
1266     ENABLE_DISABLE_VALUE_TYPE_AND_VALUE(
1267         switches::kOverscrollHistoryNavigation, "1",
1268         switches::kOverscrollHistoryNavigation, "0")
1269   },
1270 #endif
1271   {
1272     "scroll-end-effect",
1273     IDS_FLAGS_SCROLL_END_EFFECT_NAME,
1274     IDS_FLAGS_SCROLL_END_EFFECT_DESCRIPTION,
1275     kOsCrOS,
1276     ENABLE_DISABLE_VALUE_TYPE_AND_VALUE(
1277         switches::kScrollEndEffect, "1",
1278         switches::kScrollEndEffect, "0")
1279   },
1280   {
1281     "enable-touch-side-bezels",
1282     IDS_FLAGS_ENABLE_TOUCH_SIDE_BEZELS_NAME,
1283     IDS_FLAGS_ENABLE_TOUCH_SIDE_BEZELS_DESCRIPTION,
1284     kOsCrOS,
1285     ENABLE_DISABLE_VALUE_TYPE_AND_VALUE(
1286         switches::kTouchSideBezels, "1",
1287         switches::kTouchSideBezels, "0")
1288   },
1289   {
1290     "enable-no-touch-to-renderer-while-scrolling",
1291     IDS_FLAGS_ENABLE_NO_TOUCH_TO_RENDERER_WHILE_SCROLLING_NAME,
1292     IDS_FLAGS_ENABLE_NO_TOUCH_TO_RENDERER_WHILE_SCROLLING_DESCRIPTION,
1293     kOsDesktop,
1294     ENABLE_DISABLE_VALUE_TYPE_AND_VALUE(
1295         switches::kNoTouchToRendererWhileScrolling, "1",
1296         switches::kNoTouchToRendererWhileScrolling, "0")
1297   },
1298   {
1299     "enable-touch-drag-drop",
1300     IDS_FLAGS_ENABLE_TOUCH_DRAG_DROP_NAME,
1301     IDS_FLAGS_ENABLE_TOUCH_DRAG_DROP_DESCRIPTION,
1302     kOsWin | kOsCrOS,
1303     ENABLE_DISABLE_VALUE_TYPE(switches::kEnableTouchDragDrop,
1304                               switches::kDisableTouchDragDrop)
1305   },
1306   {
1307     "enable-touch-editing",
1308     IDS_FLAGS_ENABLE_TOUCH_EDITING_NAME,
1309     IDS_FLAGS_ENABLE_TOUCH_EDITING_DESCRIPTION,
1310     kOsCrOS,
1311     ENABLE_DISABLE_VALUE_TYPE(switches::kEnableTouchEditing,
1312                               switches::kDisableTouchEditing)
1313   },
1314   {
1315     "enable-rich-notifications",
1316     IDS_FLAGS_ENABLE_RICH_NOTIFICATIONS_NAME,
1317     IDS_FLAGS_ENABLE_RICH_NOTIFICATIONS_DESCRIPTION,
1318     kOsWin | kOsMac,
1319     ENABLE_DISABLE_VALUE_TYPE(
1320         message_center::switches::kEnableRichNotifications,
1321         message_center::switches::kDisableRichNotifications)
1322   },
1323   {
1324     "enable-sync-synced-notifications",
1325     IDS_FLAGS_ENABLE_SYNCED_NOTIFICATIONS_NAME,
1326     IDS_FLAGS_ENABLE_SYNCED_NOTIFICATIONS_DESCRIPTION,
1327     kOsDesktop,
1328     ENABLE_DISABLE_VALUE_TYPE(switches::kEnableSyncSyncedNotifications,
1329                               switches::kDisableSyncSyncedNotifications)
1330   },
1331   {
1332     "disable-full-history-sync",
1333     IDS_FLAGS_FULL_HISTORY_SYNC_NAME,
1334     IDS_FLAGS_FULL_HISTORY_SYNC_DESCRIPTION,
1335     kOsAll,
1336     SINGLE_VALUE_TYPE(switches::kHistoryDisableFullHistorySync)
1337   },
1338   {
1339     "enable-usermedia-screen-capture",
1340     IDS_FLAGS_ENABLE_SCREEN_CAPTURE_NAME,
1341     IDS_FLAGS_ENABLE_SCREEN_CAPTURE_DESCRIPTION,
1342     kOsDesktop,
1343     SINGLE_VALUE_TYPE(switches::kEnableUserMediaScreenCapturing)
1344   },
1345   {
1346     "enable-apps-devtool-app",
1347     IDS_FLAGS_ENABLE_APPS_DEVTOOL_APP_NAME,
1348     IDS_FLAGS_ENABLE_APPS_DEVTOOL_APP_DESCRIPTION,
1349     kOsDesktop,
1350     SINGLE_VALUE_TYPE(switches::kAppsDevtool)
1351   },
1352   {
1353     "impl-side-painting",
1354     IDS_FLAGS_IMPL_SIDE_PAINTING_NAME,
1355     IDS_FLAGS_IMPL_SIDE_PAINTING_DESCRIPTION,
1356     kOsAndroid | kOsLinux | kOsCrOS,
1357     MULTI_VALUE_TYPE(kImplSidePaintingChoices)
1358   },
1359   {
1360     "delegated-renderer",
1361     IDS_FLAGS_DELEGATED_RENDERER_NAME,
1362     IDS_FLAGS_DELEGATED_RENDERER_DESCRIPTION,
1363 #ifdef USE_AURA
1364     kOsWin | kOsLinux |
1365 #endif
1366     kOsAndroid | kOsCrOS,
1367     MULTI_VALUE_TYPE(kDelegatedRendererChoices)
1368   },
1369   {
1370     "enable-websocket-experimental-implementation",
1371     IDS_FLAGS_ENABLE_EXPERIMENTAL_WEBSOCKET_NAME,
1372     IDS_FLAGS_ENABLE_EXPERIMENTAL_WEBSOCKET_DESCRIPTION,
1373     kOsAll,
1374     SINGLE_VALUE_TYPE(switches::kEnableExperimentalWebSocket)
1375   },
1376   {
1377     "max-tiles-for-interest-area",
1378     IDS_FLAGS_MAX_TILES_FOR_INTEREST_AREA_NAME,
1379     IDS_FLAGS_MAX_TILES_FOR_INTEREST_AREA_DESCRIPTION,
1380     kOsAndroid | kOsLinux | kOsCrOS,
1381     MULTI_VALUE_TYPE(kMaxTilesForInterestAreaChoices)
1382   },
1383   {
1384     "enable-offline-mode",
1385     IDS_FLAGS_ENABLE_OFFLINE_MODE_NAME,
1386     IDS_FLAGS_ENABLE_OFFLINE_MODE_DESCRIPTION,
1387     kOsAll,
1388     SINGLE_VALUE_TYPE(switches::kEnableOfflineCacheAccess)
1389   },
1390   {
1391     "default-tile-width",
1392     IDS_FLAGS_DEFAULT_TILE_WIDTH_NAME,
1393     IDS_FLAGS_DEFAULT_TILE_WIDTH_DESCRIPTION,
1394     kOsAll,
1395     MULTI_VALUE_TYPE(kDefaultTileWidthChoices)
1396   },
1397   {
1398     "default-tile-height",
1399     IDS_FLAGS_DEFAULT_TILE_HEIGHT_NAME,
1400     IDS_FLAGS_DEFAULT_TILE_HEIGHT_DESCRIPTION,
1401     kOsAll,
1402     MULTI_VALUE_TYPE(kDefaultTileHeightChoices)
1403   },
1404   // TODO(sky): ifdef needed until focus sorted out in DesktopNativeWidgetAura.
1405 #if !defined(USE_AURA)
1406   {
1407     "track-active-visit-time",
1408     IDS_FLAGS_TRACK_ACTIVE_VISIT_TIME_NAME,
1409     IDS_FLAGS_TRACK_ACTIVE_VISIT_TIME_DESCRIPTION,
1410     kOsWin,
1411     SINGLE_VALUE_TYPE(switches::kTrackActiveVisitTime)
1412   },
1413 #endif
1414 #if defined(OS_ANDROID)
1415   {
1416     "disable-gesture-requirement-for-media-playback",
1417     IDS_FLAGS_DISABLE_GESTURE_REQUIREMENT_FOR_MEDIA_PLAYBACK_NAME,
1418     IDS_FLAGS_DISABLE_GESTURE_REQUIREMENT_FOR_MEDIA_PLAYBACK_DESCRIPTION,
1419     kOsAndroid,
1420     SINGLE_VALUE_TYPE(switches::kDisableGestureRequirementForMediaPlayback)
1421   },
1422 #endif
1423 #if defined(ENABLE_GOOGLE_NOW)
1424   {
1425     "enable-google-now",
1426     IDS_FLAGS_ENABLE_GOOGLE_NOW_INTEGRATION_NAME,
1427     IDS_FLAGS_ENABLE_GOOGLE_NOW_INTEGRATION_DESCRIPTION,
1428     kOsWin | kOsCrOS | kOsMac,
1429     SINGLE_VALUE_TYPE(switches::kEnableGoogleNowIntegration)
1430   },
1431 #endif
1432 #if defined(OS_CHROMEOS)
1433   {
1434     "enable-virtual-keyboard",
1435     IDS_FLAGS_ENABLE_VIRTUAL_KEYBOARD_NAME,
1436     IDS_FLAGS_ENABLE_VIRTUAL_KEYBOARD_DESCRIPTION,
1437     kOsCrOS,
1438     SINGLE_VALUE_TYPE(keyboard::switches::kEnableVirtualKeyboard)
1439   },
1440 #endif
1441   {
1442     "enable-simple-cache-backend",
1443     IDS_FLAGS_ENABLE_SIMPLE_CACHE_BACKEND_NAME,
1444     IDS_FLAGS_ENABLE_SIMPLE_CACHE_BACKEND_DESCRIPTION,
1445     kOsAll,
1446     MULTI_VALUE_TYPE(kSimpleCacheBackendChoices)
1447   },
1448   {
1449     "enable-tcp-fast-open",
1450     IDS_FLAGS_ENABLE_TCP_FAST_OPEN_NAME,
1451     IDS_FLAGS_ENABLE_TCP_FAST_OPEN_DESCRIPTION,
1452     kOsLinux | kOsCrOS | kOsAndroid,
1453     SINGLE_VALUE_TYPE(switches::kEnableTcpFastOpen)
1454   },
1455   {
1456     "apps-use-native-frame",
1457     IDS_FLAGS_ENABLE_NATIVE_FRAMES_FOR_APPS_NAME,
1458     IDS_FLAGS_ENABLE_NATIVE_FRAMES_FOR_APPS_DESCRIPTION,
1459     kOsMac | kOsWin,
1460     SINGLE_VALUE_TYPE(switches::kAppsUseNativeFrame)
1461   },
1462   {
1463     "enable-syncfs-directory-operation",
1464     IDS_FLAGS_ENABLE_SYNC_DIRECTORY_OPERATION_NAME,
1465     IDS_FLAGS_ENABLE_SYNC_DIRECTORY_OPERATION_DESCRIPTION,
1466     kOsAll,
1467     SINGLE_VALUE_TYPE(switches::kSyncfsEnableDirectoryOperation),
1468   },
1469   {
1470     "enable-reset-profile-settings",
1471     IDS_FLAGS_ENABLE_RESET_PROFILE_SETTINGS_NAME,
1472     IDS_FLAGS_ENABLE_RESET_PROFILE_SETTINGS_DESCRIPTION,
1473     kOsAll,
1474     SINGLE_VALUE_TYPE(switches::kEnableResetProfileSettings)
1475   },
1476   {
1477     "enable-device-discovery",
1478     IDS_FLAGS_ENABLE_DEVICE_DISCOVERY_NAME,
1479     IDS_FLAGS_ENABLE_DEVICE_DISCOVERY_DESCRIPTION,
1480     kOsDesktop,
1481     SINGLE_VALUE_TYPE(switches::kEnableDeviceDiscovery)
1482   },
1483 #if defined(OS_MACOSX)
1484   {
1485     "enable-app-list-shim",
1486     IDS_FLAGS_ENABLE_APP_LIST_SHIM_NAME,
1487     IDS_FLAGS_ENABLE_APP_LIST_SHIM_DESCRIPTION,
1488     kOsMac,
1489     SINGLE_VALUE_TYPE(switches::kEnableAppListShim)
1490   },
1491   {
1492     "enable-app-shims",
1493     IDS_FLAGS_ENABLE_APP_SHIMS_NAME,
1494     IDS_FLAGS_ENABLE_APP_SHIMS_DESCRIPTION,
1495     kOsMac,
1496     SINGLE_VALUE_TYPE(switches::kEnableAppShims)
1497   },
1498   {
1499     "enable-simplified-fullscreen",
1500     IDS_FLAGS_ENABLE_SIMPLIFIED_FULLSCREEN_NAME,
1501     IDS_FLAGS_ENABLE_SIMPLIFIED_FULLSCREEN_DESCRIPTION,
1502     kOsMac,
1503     SINGLE_VALUE_TYPE(switches::kEnableSimplifiedFullscreen)
1504   },
1505 #endif
1506 #if defined(OS_CHROMEOS) || defined(OS_WIN)
1507   {
1508     "omnibox-auto-completion-for-ime",
1509     IDS_FLAGS_ENABLE_OMNIBOX_AUTO_COMPLETION_FOR_IME_NAME,
1510     IDS_FLAGS_ENABLE_OMNIBOX_AUTO_COMPLETION_FOR_IME_DESCRIPTION,
1511     kOsCrOS | kOsWin,
1512     ENABLE_DISABLE_VALUE_TYPE(switches::kEnableOmniboxAutoCompletionForIme,
1513                               switches::kDisableOmniboxAutoCompletionForIme)
1514   },
1515 #endif
1516 #if defined(USE_AURA)
1517   {
1518     "tab-capture-upscale-quality",
1519     IDS_FLAGS_TAB_CAPTURE_UPSCALE_QUALITY_NAME,
1520     IDS_FLAGS_TAB_CAPTURE_UPSCALE_QUALITY_DESCRIPTION,
1521     kOsAll,
1522     MULTI_VALUE_TYPE(kTabCaptureUpscaleQualityChoices)
1523   },
1524   {
1525     "tab-capture-downscale-quality",
1526     IDS_FLAGS_TAB_CAPTURE_DOWNSCALE_QUALITY_NAME,
1527     IDS_FLAGS_TAB_CAPTURE_DOWNSCALE_QUALITY_DESCRIPTION,
1528     kOsAll,
1529     MULTI_VALUE_TYPE(kTabCaptureDownscaleQualityChoices)
1530   },
1531 #endif
1532   {
1533     "enable-spelling-service-feedback",
1534     IDS_FLAGS_ENABLE_SPELLING_SERVICE_FEEDBACK_NAME,
1535     IDS_FLAGS_ENABLE_SPELLING_SERVICE_FEEDBACK_DESCRIPTION,
1536     kOsAll,
1537     SINGLE_VALUE_TYPE(switches::kEnableSpellingServiceFeedback)
1538   },
1539   {
1540     "enable-webgl-draft-extensions",
1541     IDS_FLAGS_ENABLE_WEBGL_DRAFT_EXTENSIONS_NAME,
1542     IDS_FLAGS_ENABLE_WEBGL_DRAFT_EXTENSIONS_DESCRIPTION,
1543     kOsAll,
1544     SINGLE_VALUE_TYPE(switches::kEnableWebGLDraftExtensions)
1545   },
1546   {
1547     "enable-html-imports",
1548     IDS_FLAGS_ENABLE_HTML_IMPORTS_NAME,
1549     IDS_FLAGS_ENABLE_HTML_IMPORTS_DESCRIPTION,
1550     kOsAll,
1551     SINGLE_VALUE_TYPE(switches::kEnableHTMLImports)
1552   },
1553   {
1554     "high-dpi-support",
1555     IDS_FLAGS_HIDPI_NAME,
1556     IDS_FLAGS_HIDPI_DESCRIPTION,
1557     kOsWin,
1558     ENABLE_DISABLE_VALUE_TYPE_AND_VALUE(switches::kHighDPISupport,"1",
1559         switches::kHighDPISupport,"0")
1560   },
1561 #if defined(OS_CHROMEOS)
1562   {
1563     "enable-quickoffice-viewing",
1564     IDS_FLAGS_ENABLE_QUICKOFFICE_DESKTOP_VIEWING_NAME,
1565     IDS_FLAGS_ENABLE_QUICKOFFICE_DESKTOP_VIEWING_DESCRIPTION,
1566     kOsCrOS,
1567     SINGLE_VALUE_TYPE(switches::kEnableQuickofficeViewing),
1568   },
1569   {
1570     "enable-sticky-keys",
1571     IDS_FLAGS_ENABLE_STICKY_KEYS_NAME,
1572     IDS_FLAGS_ENABLE_STICKY_KEYS_DESCRIPTION,
1573     kOsCrOS,
1574     ENABLE_DISABLE_VALUE_TYPE(switches::kEnableStickyKeys,
1575                               switches::kDisableStickyKeys)
1576   },
1577 #endif
1578   {
1579     "enable-translate-settings",
1580     IDS_FLAGS_ENABLE_TRANSLATE_SETTINGS_NAME,
1581     IDS_FLAGS_ENABLE_TRANSLATE_SETTINGS_DESCRIPTION,
1582     kOsAll,
1583     SINGLE_VALUE_TYPE(switches::kEnableTranslateSettings)
1584   },
1585   {
1586     "enable-web-midi",
1587     IDS_FLAGS_ENABLE_WEB_MIDI_NAME,
1588     IDS_FLAGS_ENABLE_WEB_MIDI_DESCRIPTION,
1589     kOsMac,
1590     SINGLE_VALUE_TYPE(switches::kEnableWebMIDI)
1591   },
1592   {
1593     "enable-new-profile-management",
1594     IDS_FLAGS_ENABLE_NEW_PROFILE_MANAGEMENT_NAME,
1595     IDS_FLAGS_ENABLE_NEW_PROFILE_MANAGEMENT_DESCRIPTION,
1596     kOsWin,
1597     SINGLE_VALUE_TYPE(switches::kNewProfileManagement)
1598   },
1599   {
1600     "enable-gaia-profile-info",
1601     IDS_FLAGS_ENABLE_GAIA_PROFILE_INFO_NAME,
1602     IDS_FLAGS_ENABLE_GAIA_PROFILE_INFO_DESCRIPTION,
1603     kOsMac | kOsWin | kOsLinux,
1604     SINGLE_VALUE_TYPE(switches::kGaiaProfileInfo)
1605   },
1606 #if defined(OS_WIN)
1607   {
1608     "disable-app-launcher",
1609     IDS_FLAGS_DISABLE_APP_LIST_NAME,
1610     IDS_FLAGS_DISABLE_APP_LIST_DESCRIPTION,
1611     kOsAll,
1612     SINGLE_VALUE_TYPE(switches::kDisableAppList)
1613   },
1614 #endif
1615 #if defined(OS_CHROMEOS)
1616   {
1617     "disable-user-image-sync",
1618     IDS_FLAGS_DISABLE_USER_IMAGE_SYNC_NAME,
1619     IDS_FLAGS_DISABLE_USER_IMAGE_SYNC_DESCRIPTION,
1620     kOsCrOS,
1621     SINGLE_VALUE_TYPE(chromeos::switches::kDisableUserImageSync)
1622   },
1623 #endif
1624 #if defined(OS_ANDROID)
1625   {
1626     "enable-accessibility-tab-switcher",
1627     IDS_FLAGS_ENABLE_ACCESSIBILITY_TAB_SWITCHER_NAME,
1628     IDS_FLAGS_ENABLE_ACCESSIBILITY_TAB_SWITCHER_DESCRIPTION,
1629     kOsAndroid,
1630     SINGLE_VALUE_TYPE(switches::kEnableAccessibilityTabSwitcher)
1631   }
1632 #endif
1633 };
1634
1635 const Experiment* experiments = kExperiments;
1636 size_t num_experiments = arraysize(kExperiments);
1637
1638 // Stores and encapsulates the little state that about:flags has.
1639 class FlagsState {
1640  public:
1641   FlagsState() : needs_restart_(false) {}
1642   void ConvertFlagsToSwitches(FlagsStorage* flags_storage,
1643                               CommandLine* command_line);
1644   bool IsRestartNeededToCommitChanges();
1645   void SetExperimentEnabled(
1646       FlagsStorage* flags_storage,
1647       const std::string& internal_name,
1648       bool enable);
1649   void RemoveFlagsSwitches(
1650       std::map<std::string, CommandLine::StringType>* switch_list);
1651   void ResetAllFlags(FlagsStorage* flags_storage);
1652   void reset();
1653
1654   // Returns the singleton instance of this class
1655   static FlagsState* GetInstance() {
1656     return Singleton<FlagsState>::get();
1657   }
1658
1659  private:
1660   bool needs_restart_;
1661   std::map<std::string, std::string> flags_switches_;
1662
1663   DISALLOW_COPY_AND_ASSIGN(FlagsState);
1664 };
1665
1666 // Adds the internal names for the specified experiment to |names|.
1667 void AddInternalName(const Experiment& e, std::set<std::string>* names) {
1668   if (e.type == Experiment::SINGLE_VALUE) {
1669     names->insert(e.internal_name);
1670   } else {
1671     DCHECK(e.type == Experiment::MULTI_VALUE ||
1672            e.type == Experiment::ENABLE_DISABLE_VALUE);
1673     for (int i = 0; i < e.num_choices; ++i)
1674       names->insert(e.NameForChoice(i));
1675   }
1676 }
1677
1678 // Confirms that an experiment is valid, used in a DCHECK in
1679 // SanitizeList below.
1680 bool ValidateExperiment(const Experiment& e) {
1681   switch (e.type) {
1682     case Experiment::SINGLE_VALUE:
1683       DCHECK_EQ(0, e.num_choices);
1684       DCHECK(!e.choices);
1685       break;
1686     case Experiment::MULTI_VALUE:
1687       DCHECK_GT(e.num_choices, 0);
1688       DCHECK(e.choices);
1689       DCHECK(e.choices[0].command_line_switch);
1690       DCHECK_EQ('\0', e.choices[0].command_line_switch[0]);
1691       break;
1692     case Experiment::ENABLE_DISABLE_VALUE:
1693       DCHECK_EQ(3, e.num_choices);
1694       DCHECK(!e.choices);
1695       DCHECK(e.command_line_switch);
1696       DCHECK(e.command_line_value);
1697       DCHECK(e.disable_command_line_switch);
1698       DCHECK(e.disable_command_line_value);
1699       break;
1700     default:
1701       NOTREACHED();
1702   }
1703   return true;
1704 }
1705
1706 // Removes all experiments from prefs::kEnabledLabsExperiments that are
1707 // unknown, to prevent this list to become very long as experiments are added
1708 // and removed.
1709 void SanitizeList(FlagsStorage* flags_storage) {
1710   std::set<std::string> known_experiments;
1711   for (size_t i = 0; i < num_experiments; ++i) {
1712     DCHECK(ValidateExperiment(experiments[i]));
1713     AddInternalName(experiments[i], &known_experiments);
1714   }
1715
1716   std::set<std::string> enabled_experiments = flags_storage->GetFlags();
1717
1718   std::set<std::string> new_enabled_experiments;
1719   std::set_intersection(
1720       known_experiments.begin(), known_experiments.end(),
1721       enabled_experiments.begin(), enabled_experiments.end(),
1722       std::inserter(new_enabled_experiments, new_enabled_experiments.begin()));
1723
1724   if (new_enabled_experiments != enabled_experiments)
1725     flags_storage->SetFlags(new_enabled_experiments);
1726 }
1727
1728 void GetSanitizedEnabledFlags(
1729     FlagsStorage* flags_storage, std::set<std::string>* result) {
1730   SanitizeList(flags_storage);
1731   *result = flags_storage->GetFlags();
1732 }
1733
1734 // Variant of GetSanitizedEnabledFlags that also removes any flags that aren't
1735 // enabled on the current platform.
1736 void GetSanitizedEnabledFlagsForCurrentPlatform(
1737     FlagsStorage* flags_storage, std::set<std::string>* result) {
1738   GetSanitizedEnabledFlags(flags_storage, result);
1739
1740   // Filter out any experiments that aren't enabled on the current platform.  We
1741   // don't remove these from prefs else syncing to a platform with a different
1742   // set of experiments would be lossy.
1743   std::set<std::string> platform_experiments;
1744   int current_platform = GetCurrentPlatform();
1745   for (size_t i = 0; i < num_experiments; ++i) {
1746     if (experiments[i].supported_platforms & current_platform)
1747       AddInternalName(experiments[i], &platform_experiments);
1748 #if defined(OS_CHROMEOS)
1749     if (experiments[i].supported_platforms & kOsCrOSOwnerOnly)
1750       AddInternalName(experiments[i], &platform_experiments);
1751 #endif
1752   }
1753
1754   std::set<std::string> new_enabled_experiments;
1755   std::set_intersection(
1756       platform_experiments.begin(), platform_experiments.end(),
1757       result->begin(), result->end(),
1758       std::inserter(new_enabled_experiments, new_enabled_experiments.begin()));
1759
1760   result->swap(new_enabled_experiments);
1761 }
1762
1763 // Returns the Value representing the choice data in the specified experiment.
1764 Value* CreateChoiceData(const Experiment& experiment,
1765                         const std::set<std::string>& enabled_experiments) {
1766   DCHECK(experiment.type == Experiment::MULTI_VALUE ||
1767          experiment.type == Experiment::ENABLE_DISABLE_VALUE);
1768   ListValue* result = new ListValue;
1769   for (int i = 0; i < experiment.num_choices; ++i) {
1770     DictionaryValue* value = new DictionaryValue;
1771     const std::string name = experiment.NameForChoice(i);
1772     value->SetString("internal_name", name);
1773     value->SetString("description", experiment.DescriptionForChoice(i));
1774     value->SetBoolean("selected", enabled_experiments.count(name) > 0);
1775     result->Append(value);
1776   }
1777   return result;
1778 }
1779
1780 }  // namespace
1781
1782 std::string Experiment::NameForChoice(int index) const {
1783   DCHECK(type == Experiment::MULTI_VALUE ||
1784          type == Experiment::ENABLE_DISABLE_VALUE);
1785   DCHECK_LT(index, num_choices);
1786   return std::string(internal_name) + testing::kMultiSeparator +
1787          base::IntToString(index);
1788 }
1789
1790 string16 Experiment::DescriptionForChoice(int index) const {
1791   DCHECK(type == Experiment::MULTI_VALUE ||
1792          type == Experiment::ENABLE_DISABLE_VALUE);
1793   DCHECK_LT(index, num_choices);
1794   int description_id;
1795   if (type == Experiment::ENABLE_DISABLE_VALUE) {
1796     const int kEnableDisableDescriptionIds[] = {
1797       IDS_GENERIC_EXPERIMENT_CHOICE_DEFAULT,
1798       IDS_GENERIC_EXPERIMENT_CHOICE_ENABLED,
1799       IDS_GENERIC_EXPERIMENT_CHOICE_DISABLED,
1800     };
1801     description_id = kEnableDisableDescriptionIds[index];
1802   } else {
1803     description_id = choices[index].description_id;
1804   }
1805   return l10n_util::GetStringUTF16(description_id);
1806 }
1807
1808 void ConvertFlagsToSwitches(FlagsStorage* flags_storage,
1809                             CommandLine* command_line) {
1810   FlagsState::GetInstance()->ConvertFlagsToSwitches(flags_storage,
1811                                                     command_line);
1812 }
1813
1814 bool AreSwitchesIdenticalToCurrentCommandLine(
1815     const CommandLine& new_cmdline, const CommandLine& active_cmdline) {
1816   std::set<CommandLine::StringType> new_flags =
1817       ExtractFlagsFromCommandLine(new_cmdline);
1818   std::set<CommandLine::StringType> active_flags =
1819       ExtractFlagsFromCommandLine(active_cmdline);
1820
1821   // Needed because std::equal doesn't check if the 2nd set is empty.
1822   if (new_flags.size() != active_flags.size())
1823     return false;
1824
1825   return std::equal(new_flags.begin(), new_flags.end(), active_flags.begin());
1826 }
1827
1828 void GetFlagsExperimentsData(FlagsStorage* flags_storage,
1829                              FlagAccess access,
1830                              base::ListValue* supported_experiments,
1831                              base::ListValue* unsupported_experiments) {
1832   std::set<std::string> enabled_experiments;
1833   GetSanitizedEnabledFlags(flags_storage, &enabled_experiments);
1834
1835   int current_platform = GetCurrentPlatform();
1836
1837   for (size_t i = 0; i < num_experiments; ++i) {
1838     const Experiment& experiment = experiments[i];
1839
1840     DictionaryValue* data = new DictionaryValue();
1841     data->SetString("internal_name", experiment.internal_name);
1842     data->SetString("name",
1843                     l10n_util::GetStringUTF16(experiment.visible_name_id));
1844     data->SetString("description",
1845                     l10n_util::GetStringUTF16(
1846                         experiment.visible_description_id));
1847
1848     ListValue* supported_platforms = new ListValue();
1849     AddOsStrings(experiment.supported_platforms, supported_platforms);
1850     data->Set("supported_platforms", supported_platforms);
1851
1852     switch (experiment.type) {
1853       case Experiment::SINGLE_VALUE:
1854         data->SetBoolean(
1855             "enabled",
1856             enabled_experiments.count(experiment.internal_name) > 0);
1857         break;
1858       case Experiment::MULTI_VALUE:
1859       case Experiment::ENABLE_DISABLE_VALUE:
1860         data->Set("choices", CreateChoiceData(experiment, enabled_experiments));
1861         break;
1862       default:
1863         NOTREACHED();
1864     }
1865
1866     bool supported = (experiment.supported_platforms & current_platform) != 0;
1867 #if defined(OS_CHROMEOS)
1868     if (access == kOwnerAccessToFlags &&
1869         (experiment.supported_platforms & kOsCrOSOwnerOnly) != 0) {
1870       supported = true;
1871     }
1872 #endif
1873     if (supported)
1874       supported_experiments->Append(data);
1875     else
1876       unsupported_experiments->Append(data);
1877   }
1878 }
1879
1880 bool IsRestartNeededToCommitChanges() {
1881   return FlagsState::GetInstance()->IsRestartNeededToCommitChanges();
1882 }
1883
1884 void SetExperimentEnabled(FlagsStorage* flags_storage,
1885                           const std::string& internal_name,
1886                           bool enable) {
1887   FlagsState::GetInstance()->SetExperimentEnabled(flags_storage,
1888                                                   internal_name, enable);
1889 }
1890
1891 void RemoveFlagsSwitches(
1892     std::map<std::string, CommandLine::StringType>* switch_list) {
1893   FlagsState::GetInstance()->RemoveFlagsSwitches(switch_list);
1894 }
1895
1896 void ResetAllFlags(FlagsStorage* flags_storage) {
1897   FlagsState::GetInstance()->ResetAllFlags(flags_storage);
1898 }
1899
1900 int GetCurrentPlatform() {
1901 #if defined(OS_MACOSX)
1902   return kOsMac;
1903 #elif defined(OS_WIN)
1904   return kOsWin;
1905 #elif defined(OS_CHROMEOS)  // Needs to be before the OS_LINUX check.
1906   return kOsCrOS;
1907 #elif defined(OS_LINUX) || defined(OS_OPENBSD)
1908   return kOsLinux;
1909 #elif defined(OS_ANDROID)
1910   return kOsAndroid;
1911 #else
1912 #error Unknown platform
1913 #endif
1914 }
1915
1916 void RecordUMAStatistics(FlagsStorage* flags_storage) {
1917   std::set<std::string> flags = flags_storage->GetFlags();
1918   for (std::set<std::string>::iterator it = flags.begin(); it != flags.end();
1919        ++it) {
1920     std::string action("AboutFlags_");
1921     action += *it;
1922     content::RecordComputedAction(action);
1923   }
1924   // Since flag metrics are recorded every startup, add a tick so that the
1925   // stats can be made meaningful.
1926   if (flags.size())
1927     content::RecordAction(UserMetricsAction("AboutFlags_StartupTick"));
1928   content::RecordAction(UserMetricsAction("StartupTick"));
1929 }
1930
1931 //////////////////////////////////////////////////////////////////////////////
1932 // FlagsState implementation.
1933
1934 namespace {
1935
1936 typedef std::map<std::string, std::pair<std::string, std::string> >
1937     NameToSwitchAndValueMap;
1938
1939 void SetFlagToSwitchMapping(const std::string& key,
1940                             const std::string& switch_name,
1941                             const std::string& switch_value,
1942                             NameToSwitchAndValueMap* name_to_switch_map) {
1943   DCHECK(name_to_switch_map->end() == name_to_switch_map->find(key));
1944   (*name_to_switch_map)[key] = std::make_pair(switch_name, switch_value);
1945 }
1946
1947 void FlagsState::ConvertFlagsToSwitches(
1948     FlagsStorage* flags_storage, CommandLine* command_line) {
1949   if (command_line->HasSwitch(switches::kNoExperiments))
1950     return;
1951
1952   std::set<std::string> enabled_experiments;
1953
1954   GetSanitizedEnabledFlagsForCurrentPlatform(flags_storage,
1955                                              &enabled_experiments);
1956
1957   NameToSwitchAndValueMap name_to_switch_map;
1958   for (size_t i = 0; i < num_experiments; ++i) {
1959     const Experiment& e = experiments[i];
1960     if (e.type == Experiment::SINGLE_VALUE) {
1961       SetFlagToSwitchMapping(e.internal_name, e.command_line_switch,
1962                              e.command_line_value, &name_to_switch_map);
1963     } else if (e.type == Experiment::MULTI_VALUE) {
1964       for (int j = 0; j < e.num_choices; ++j) {
1965         SetFlagToSwitchMapping(e.NameForChoice(j),
1966                                e.choices[j].command_line_switch,
1967                                e.choices[j].command_line_value,
1968                                &name_to_switch_map);
1969       }
1970     } else {
1971       DCHECK_EQ(e.type, Experiment::ENABLE_DISABLE_VALUE);
1972       SetFlagToSwitchMapping(e.NameForChoice(0), std::string(), std::string(),
1973                              &name_to_switch_map);
1974       SetFlagToSwitchMapping(e.NameForChoice(1), e.command_line_switch,
1975                              e.command_line_value, &name_to_switch_map);
1976       SetFlagToSwitchMapping(e.NameForChoice(2), e.disable_command_line_switch,
1977                              e.disable_command_line_value, &name_to_switch_map);
1978     }
1979   }
1980
1981   command_line->AppendSwitch(switches::kFlagSwitchesBegin);
1982   flags_switches_.insert(
1983       std::pair<std::string, std::string>(switches::kFlagSwitchesBegin,
1984                                           std::string()));
1985   for (std::set<std::string>::iterator it = enabled_experiments.begin();
1986        it != enabled_experiments.end();
1987        ++it) {
1988     const std::string& experiment_name = *it;
1989     NameToSwitchAndValueMap::const_iterator name_to_switch_it =
1990         name_to_switch_map.find(experiment_name);
1991     if (name_to_switch_it == name_to_switch_map.end()) {
1992       NOTREACHED();
1993       continue;
1994     }
1995
1996     const std::pair<std::string, std::string>&
1997         switch_and_value_pair = name_to_switch_it->second;
1998
1999     command_line->AppendSwitchASCII(switch_and_value_pair.first,
2000                                     switch_and_value_pair.second);
2001     flags_switches_[switch_and_value_pair.first] = switch_and_value_pair.second;
2002   }
2003   command_line->AppendSwitch(switches::kFlagSwitchesEnd);
2004   flags_switches_.insert(
2005       std::pair<std::string, std::string>(switches::kFlagSwitchesEnd,
2006                                           std::string()));
2007 }
2008
2009 bool FlagsState::IsRestartNeededToCommitChanges() {
2010   return needs_restart_;
2011 }
2012
2013 void FlagsState::SetExperimentEnabled(FlagsStorage* flags_storage,
2014                                       const std::string& internal_name,
2015                                       bool enable) {
2016   size_t at_index = internal_name.find(testing::kMultiSeparator);
2017   if (at_index != std::string::npos) {
2018     DCHECK(enable);
2019     // We're being asked to enable a multi-choice experiment. Disable the
2020     // currently selected choice.
2021     DCHECK_NE(at_index, 0u);
2022     const std::string experiment_name = internal_name.substr(0, at_index);
2023     SetExperimentEnabled(flags_storage, experiment_name, false);
2024
2025     // And enable the new choice, if it is not the default first choice.
2026     if (internal_name != experiment_name + "@0") {
2027       std::set<std::string> enabled_experiments;
2028       GetSanitizedEnabledFlags(flags_storage, &enabled_experiments);
2029       needs_restart_ |= enabled_experiments.insert(internal_name).second;
2030       flags_storage->SetFlags(enabled_experiments);
2031     }
2032     return;
2033   }
2034
2035   std::set<std::string> enabled_experiments;
2036   GetSanitizedEnabledFlags(flags_storage, &enabled_experiments);
2037
2038   const Experiment* e = NULL;
2039   for (size_t i = 0; i < num_experiments; ++i) {
2040     if (experiments[i].internal_name == internal_name) {
2041       e = experiments + i;
2042       break;
2043     }
2044   }
2045   DCHECK(e);
2046
2047   if (e->type == Experiment::SINGLE_VALUE) {
2048     if (enable)
2049       needs_restart_ |= enabled_experiments.insert(internal_name).second;
2050     else
2051       needs_restart_ |= (enabled_experiments.erase(internal_name) > 0);
2052   } else {
2053     if (enable) {
2054       // Enable the first choice.
2055       needs_restart_ |= enabled_experiments.insert(e->NameForChoice(0)).second;
2056     } else {
2057       // Find the currently enabled choice and disable it.
2058       for (int i = 0; i < e->num_choices; ++i) {
2059         std::string choice_name = e->NameForChoice(i);
2060         if (enabled_experiments.find(choice_name) !=
2061             enabled_experiments.end()) {
2062           needs_restart_ = true;
2063           enabled_experiments.erase(choice_name);
2064           // Continue on just in case there's a bug and more than one
2065           // experiment for this choice was enabled.
2066         }
2067       }
2068     }
2069   }
2070
2071   flags_storage->SetFlags(enabled_experiments);
2072 }
2073
2074 void FlagsState::RemoveFlagsSwitches(
2075     std::map<std::string, CommandLine::StringType>* switch_list) {
2076   for (std::map<std::string, std::string>::const_iterator
2077            it = flags_switches_.begin(); it != flags_switches_.end(); ++it) {
2078     switch_list->erase(it->first);
2079   }
2080 }
2081
2082 void FlagsState::ResetAllFlags(FlagsStorage* flags_storage) {
2083   needs_restart_ = true;
2084
2085   std::set<std::string> no_experiments;
2086   flags_storage->SetFlags(no_experiments);
2087 }
2088
2089 void FlagsState::reset() {
2090   needs_restart_ = false;
2091   flags_switches_.clear();
2092 }
2093
2094 }  // namespace
2095
2096 namespace testing {
2097
2098 // WARNING: '@' is also used in the html file. If you update this constant you
2099 // also need to update the html file.
2100 const char kMultiSeparator[] = "@";
2101
2102 void ClearState() {
2103   FlagsState::GetInstance()->reset();
2104 }
2105
2106 void SetExperiments(const Experiment* e, size_t count) {
2107   if (!e) {
2108     experiments = kExperiments;
2109     num_experiments = arraysize(kExperiments);
2110   } else {
2111     experiments = e;
2112     num_experiments = count;
2113   }
2114 }
2115
2116 const Experiment* GetExperiments(size_t* count) {
2117   *count = num_experiments;
2118   return experiments;
2119 }
2120
2121 }  // namespace testing
2122
2123 }  // namespace about_flags