[Android] Reland "Provide unhandled tap event notifications"

[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

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=266732

[jdduke (slow), 2014-04-28 18:24:18]

The CQ bit was checked by jdduke@chromium.org

[commit-bot: I haz the power, 2014-04-28 18:26:26]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/jdduke@chromium.org/256213002/1

[commit-bot: I haz the power, 2014-04-28 19:02:36]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2014-04-28 19:02:37]

Try jobs failed on following builders:
  tryserver.chromium on android_clang_dbg

[jdduke (slow), 2014-04-28 19:52:41]

The CQ bit was checked by jdduke@chromium.org

[commit-bot: I haz the power, 2014-04-28 19:53:02]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/jdduke@chromium.org/256213002/20001

[commit-bot: I haz the power, 2014-04-29 01:52:19]

Change committed as 266732

[Michael Achenbach, 2014-04-29 10:32:51]

A revert of this CL has been created in
https://codereview.chromium.org/259073005/ by machenbach@chromium.org.

The reason for reverting is: The test TouchCursorInTextfieldTest is failing
flakily on Linux ChromiumOS Tests (2):

http://build.chromium.org/p/chromium.chromiumos/builders/Linux%20ChromiumOS%2...

The precondition CL crrev.com/218633008 also got previously reverted..