[Android] Send TapCancel if necessary when a touch gesture is consumed

When a TouchStart is unconsumed by Javascript, a GestureTapDown is sent
immediately, potentially followed by a GestureShowPress.  Fix the case where
the subsequent Touch{Move,End} is consumed by Javascript by synthesizing
a GestureTapCancel.

BUG=330718

Review URL: https://codereview.chromium.org/120203003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@242553 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 242553