GitLab

Once WillShutdown is called the InputHandlerProxy object should be destroyed
since it is no longer valid.

BUG=775483

Change-Id: I3dc1cf7d7295ff08bbcec3d8ee2b12690961af2e
Reviewed-on: https://chromium-review.googlesource.com/725860Reviewed-by: Mustaq Ahmed <mustaq@chromium.org>
Commit-Queue: Dave Tapuska <dtapuska@chromium.org>
Cr-Commit-Position: refs/heads/master@{#509894}