[Android WebView] Disable fallback ticks when paused or window invisible
Apps call onPause/onResume to explicitly request
pausing/resuming per webview processing. But apps are not
required to call them.
Also window (not view) becomes invisible when the for
example, an app is put into the background.
Should use these signals to disable fallback tick, which is
normally used to ensure offscreen webviews still make
progress.
BUG=276104
NOTRY=true
Review URL: https://chromiumcodereview.appspot.com/
23004005
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@218466 0039d316-1c4b-4281-b951-d872f2087c98