Revert of Blink roll 171141:171225 (https://codereview.chromium.org/232453002/)

Revert of Blink roll 171141:171225 (https://codereview.chromium.org/232453002/)

Reason for revert:
Chrome for ChromeOS build is failing:
chromeos-chrome-36.0.1934.0_alpha-r1: ../../../../../../../home/chrome-bot/chrome_root/src/third_party/WebKit/Source/core/dom/CharacterData.cpp: In member function 'void WebCore::CharacterData::replaceData(unsigned int, unsigned int, const WTF::String&, WebCore::ExceptionState&)':
chromeos-chrome-36.0.1934.0_alpha-r1: ../../../../../../../home/chrome-bot/chrome_root/src/third_party/WebKit/Source/core/dom/CharacterData.cpp:146:36: error: 'realCount' may be used uninitialized in this function [-Werror=maybe-uninitialized]
chromeos-chrome-36.0.1934.0_alpha-r1:      newStr.remove(offset, realCount);
chromeos-chrome-36.0.1934.0_alpha-r1:                                     ^
chromeos-chrome-36.0.1934.0_alpha-r1: ../../../../../../../home/chrome-bot/chrome_root/src/third_party/WebKit/Source/core/dom/CharacterData.cpp: In member function 'void WebCore::CharacterData::deleteData(unsigned int, unsigned int, WebCore::ExceptionState&, WebCore::CharacterData::RecalcStyleBehavior)':
chromeos-chrome-36.0.1934.0_alpha-r1: ../../../../../../../home/chrome-bot/chrome_root/src/third_party/WebKit/Source/core/dom/CharacterData.cpp:132:36: error: 'realCount' may be used uninitialized in this function [-Werror=maybe-uninitialized]
chromeos-chrome-36.0.1934.0_alpha-r1:      newStr.remove(offset, realCount);
chromeos-chrome-36.0.1934.0_alpha-r1:                                     ^

Original issue's description:
> Blink roll 171141:171225
>
> http://build.chromium.org/f/chromium/perf/dashboard/ui/changelog_blink.html?url=/trunk&range=171141:171225&mode=html
> TBR=
> BUG=
>
> Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=262942

TBR=eseidel@chromium.org
NOTREECHECKS=true
NOTRY=true
BUG=

Review URL: https://codereview.chromium.org/233003002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@262950 0039d316-1c4b-4281-b951-d872f2087c98