Add end-to-end tests for the sticky keys accessibility feature.

BUG=263430
TEST=this is the test

Review URL: https://codereview.chromium.org/29113004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@230004 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 230004
Move ToggleMaximized impl to ash and remove ShellDelegate::ToggleMaximized

BUG=272460

Review URL: https://codereview.chromium.org/29153006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@230005 0039d316-1c4b-4281-b951-d872f2087c98
Fix and re-enable the tab_capture_performance_tests for AURA and MAC.
There are two fixes in here:

1. The test framework doesn't terminate if there is no idle time, so make sure that
   idle time is created by stopping capturing and animation.

2. Aura generates unexpected tracing events. Basically, it looks like it's using the
   GPU even when it doesn't. Disable the check that tries to assert that we're using
   software when we ask for software and vice versa.

BUG=308236

Review URL: https://codereview.chromium.org/29633002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@230006 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 230005
SVN changes up to revision 230006