Allow the OSX App Launcher to appear over other fullscreen apps in Mavericks.

On Mavericks with the "Displays have separate Spaces" option, OSX has
stopped switching out of the fullscreen space when activating a window
in the non-active application, other than by clicking its Dock icon.
Since the app launcher Dock icon is not Chrome, this can leave a user in
fullscreen with the app launcher window obscured.

This CL overrides a private method, -[NSWindow
_allowedInOtherAppsFullScreenSpaceWithCollectionBehavior:] to allow the
app launcher to appear on top of other applications in fullscreen. Then,
since clicking that window will make Chrome active, subsequent window
activations will successfully switch the user out of the fullscreen
space.

BUG=326405

Review URL: https://codereview.chromium.org/143753002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@245996 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 245996