Disable a test file for cast_unittest

This file causes compiler warnings so disable it.

R=justinlin@chromium.org

Review URL: https://codereview.chromium.org/25928002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@226837 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 226837
Fix ImmersiveModeControllerAshTestWithBrowserView.Layout

BUG=302908
TEST=ImmersiveModeControllerAshTestWithBrowserView.Layout is not flaky anymore

Review URL: https://codereview.chromium.org/25607007

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@226838 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 226838