The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/8a5175d4d41a509d02476d3d2dcdb9125a34a3c6

commit 8a5175d4d41a509d02476d3d2dcdb9125a34a3c6
Author: James Cook <jamescook@chromium.org>
Date: Thu Nov 29 15:11:27 2018

Move ViewsDelegate::NotifyAccessibilityEvent to an observer pattern

Introduce AXEventManager to maintain an ObserverList of objects
interested in views accessibility events.

This makes testing easier by eliminating the need for several
TestViewsDelegates.

BUG= 908884 
TEST=views_unittests, views_mus_unittests, browser_tests

Change-Id: Ic7017444fec7e694675ad675e0fefaf78b622130
Reviewed-on: https://chromium-review.googlesource.com/c/1352265
Reviewed-by: Dominic Mazzoni <dmazzoni@chromium.org>
Reviewed-by: Scott Violet <sky@chromium.org>
Commit-Queue: James Cook <jamescook@chromium.org>
Cr-Commit-Position: refs/heads/master@{#612192}
[modify] https://crrev.com/8a5175d4d41a509d02476d3d2dcdb9125a34a3c6/ash/test/ash_test_views_delegate.cc
[modify] https://crrev.com/8a5175d4d41a509d02476d3d2dcdb9125a34a3c6/ash/test/ash_test_views_delegate.h
[modify] https://crrev.com/8a5175d4d41a509d02476d3d2dcdb9125a34a3c6/chrome/browser/ui/aura/accessibility/automation_manager_aura.cc
[modify] https://crrev.com/8a5175d4d41a509d02476d3d2dcdb9125a34a3c6/chrome/browser/ui/aura/accessibility/automation_manager_aura.h
[modify] https://crrev.com/8a5175d4d41a509d02476d3d2dcdb9125a34a3c6/chrome/browser/ui/views/chrome_views_delegate.cc
[modify] https://crrev.com/8a5175d4d41a509d02476d3d2dcdb9125a34a3c6/chrome/browser/ui/views/chrome_views_delegate.h
[modify] https://crrev.com/8a5175d4d41a509d02476d3d2dcdb9125a34a3c6/chrome/browser/ui/views/tabs/tab_strip_unittest.cc
[modify] https://crrev.com/8a5175d4d41a509d02476d3d2dcdb9125a34a3c6/chrome/test/views/chrome_views_test_base.cc
[modify] https://crrev.com/8a5175d4d41a509d02476d3d2dcdb9125a34a3c6/chrome/test/views/chrome_views_test_base.h
[modify] https://crrev.com/8a5175d4d41a509d02476d3d2dcdb9125a34a3c6/ui/views/BUILD.gn
[add] https://crrev.com/8a5175d4d41a509d02476d3d2dcdb9125a34a3c6/ui/views/accessibility/ax_event_manager.cc
[add] https://crrev.com/8a5175d4d41a509d02476d3d2dcdb9125a34a3c6/ui/views/accessibility/ax_event_manager.h
[add] https://crrev.com/8a5175d4d41a509d02476d3d2dcdb9125a34a3c6/ui/views/accessibility/ax_event_observer.cc
[add] https://crrev.com/8a5175d4d41a509d02476d3d2dcdb9125a34a3c6/ui/views/accessibility/ax_event_observer.h
[modify] https://crrev.com/8a5175d4d41a509d02476d3d2dcdb9125a34a3c6/ui/views/accessibility/view_ax_platform_node_delegate_unittest.cc
[modify] https://crrev.com/8a5175d4d41a509d02476d3d2dcdb9125a34a3c6/ui/views/controls/slider_unittest.cc
[modify] https://crrev.com/8a5175d4d41a509d02476d3d2dcdb9125a34a3c6/ui/views/mus/ax_remote_host.cc
[modify] https://crrev.com/8a5175d4d41a509d02476d3d2dcdb9125a34a3c6/ui/views/mus/ax_remote_host.h
[modify] https://crrev.com/8a5175d4d41a509d02476d3d2dcdb9125a34a3c6/ui/views/mus/ax_remote_host_unittest.cc
[modify] https://crrev.com/8a5175d4d41a509d02476d3d2dcdb9125a34a3c6/ui/views/mus/mus_client.h
[modify] https://crrev.com/8a5175d4d41a509d02476d3d2dcdb9125a34a3c6/ui/views/mus/mus_views_delegate.cc
[modify] https://crrev.com/8a5175d4d41a509d02476d3d2dcdb9125a34a3c6/ui/views/mus/mus_views_delegate.h
[modify] https://crrev.com/8a5175d4d41a509d02476d3d2dcdb9125a34a3c6/ui/views/view.cc
[modify] https://crrev.com/8a5175d4d41a509d02476d3d2dcdb9125a34a3c6/ui/views/views_delegate.cc
[modify] https://crrev.com/8a5175d4d41a509d02476d3d2dcdb9125a34a3c6/ui/views/views_delegate.h