Disable ImmersiveModeControllerAshTestWithBrowserView.Layout. Flaky.

Test introduced in r226182.

BUG=302908, 295758
TBR=pkotwicz@chromium.org

Review URL: https://codereview.chromium.org/25474004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@226431 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 226431