Revert 233946 "Events ignoring ack disposition receive synthetic..."

android test failures

http://build.chromium.org/p/chromium.linux/builders/Android%20Tests%20%28dbg%29/builds/16097

> Events ignoring ack disposition receive synthetic acks.
> 
> Logic to handle events which ignore ack disposition has moved from the
> |GestureEventFilter| to the |ImmediateInputRouter|, and |WebInputEventTraits|.
> 
> This will allow us to make more events ignore their ack disposition, including
> touch events.
> 
> Gesture event types which will eventually ignore their ack disposition include 
> Tap, ScrollBegin, PinchBegin, PinchEnd, etc.
> 
> BUG=302852,275611
> TEST=ImmediateInputRouterTest.EventsIgnoringAckDispositionDontWaitForAcks,
> ImmediateInputRouterTest.EventsIgnoringAckDispositionStayInOrder
> 
> Review URL: https://codereview.chromium.org/44983003

TBR=tdresser@chromium.org

Review URL: https://codereview.chromium.org/66283005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@233962 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 233962