touch: Coalesce touch-events, and remove the touch-event queue from the gesture recognizer.

The major changes in this CL:
 * Remove the touch-event queue and the relevant code from the gesture
   recognizer. This is no longer necessary since there is a new queue maintained
   by the RenderWidgetHost.
 * Touch events are now coalesced in the queue when appropriate.
 * Create a list of ui::TouchEvents out of the processed/coalesced
   WebTouchEvents and feed those to the gesture recognizer.
 * Tests.
 * Remove asynchronous event-processing in ui::Events.

BUG=138153, 110231
[email protected] (content_browser.gypi)

Review URL: https://codereview.chromium.org/11188012

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@162518 0039d316-1c4b-4281-b951-d872f2087c98
22 files changed