Fix ownership bug with ViewObserver::OnViewInputEvent

Fix ownership bug with ViewObserver::OnViewInputEvent

It needs to take a const EventPtr& otherwise the first observer owns
the event and all others get NULL.

BUG=365012
TEST=none
R=ben@chromium.org

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=276012

[Ben Goodger (Google), 2014-06-09 20:34:18]

lgtm

[sky, 2014-06-09 20:35:22]

The CQ bit was checked by sky@chromium.org

[commit-bot: I haz the power, 2014-06-09 20:36:45]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/sky@chromium.org/324753002/1

[sky, 2014-06-09 21:47:49]

The CQ bit was checked by sky@chromium.org

[sky, 2014-06-09 21:48:13]

The CQ bit was unchecked by sky@chromium.org

[sky, 2014-06-09 21:55:27]

The CQ bit was checked by sky@chromium.org

[commit-bot: I haz the power, 2014-06-09 21:58:42]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/sky@chromium.org/324753002/20001

[commit-bot: I haz the power, 2014-06-10 11:41:06]

FYI, CQ is re-trying this CL (attempt #1).
The failing builders are:
  android_clang_dbg on tryserver.chromium
(http://build.chromium.org/p/tryserver.chromium/builders/android_clang_dbg/bui...)

[commit-bot: I haz the power, 2014-06-10 13:30:35]

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

[commit-bot: I haz the power, 2014-06-10 13:30:36]

Try jobs failed on following builders:
  android_clang_dbg on tryserver.chromium
(http://build.chromium.org/p/tryserver.chromium/builders/android_clang_dbg/bui...)

[sky, 2014-06-10 13:40:41]

Committed patchset #2 manually as r276012 (presubmit successful).