GitLab

Added special container for background on lock screen.
Background view can now be created in specific container.
Disabled lock screen wallpaper implementation based on serving PNG image via data source.

BUG=136853,137581
TEST=Lock screen on multimonitor configuration. Check that windows on secondary display are hidden with background.

Review URL: https://chromiumcodereview.appspot.com/10810039

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@149869 0039d316-1c4b-4281-b951-d872f2087c98