[Android] Reland "Provide unhandled tap event notifications"
Allow notifications of unhandled taps via the GestureStateListener. This change
makes GestureTap events blocking, but there are several use-cases for which this
will be necessary, e.g., WebView and contextual search.
This was landed in r26143 and reverted in r261470 due to to a failure in
TouchEditableImplAuraTest.TouchCursorInTextfieldTest. The test has been fixed
and reviewed previously in crrev.com/
218633008.
BUG=355154
TBR=sky@chromium.org
Review URL: https://codereview.chromium.org/
256213002
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@266732 0039d316-1c4b-4281-b951-d872f2087c98