GitLab

As transient logic has been moved outside of aura it doesn't make
sense for these methods to be in WindowObserver anymore. Instead they
have been added to TransientWindowManager.

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

Review URL: https://codereview.chromium.org/132013004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@244176 0039d316-1c4b-4281-b951-d872f2087c98