Reviewed by Darin Adler.

        AVPlayerLayer is adding a "fade" animation during Safari full-screen
        https://bugs.webkit.org/show_bug.cgi?id=62433

        CoreAnimation will add default animations when certain properties are changed, unless
        those changes are wrapped in a CATransaction which has had its disableActions property set
        to true.  Wrap each of these three property changes in a CATransaction and disable its actions,
        so that the default "fade" animation is not created in response.

        * UIProcess/mac/WKFullScreenWindowController.mm:
        (-[WKFullScreenWindowController enterFullScreen:]): Wrap with CATransaction.
        (-[WKFullScreenWindowController _swapView:with:]): Ditto:
        * WebProcess/FullScreen/mac/WebFullScreenManagerMac.mm:
        (WebKit::WebFullScreenManagerMac::setRootFullScreenLayer): Ditto.

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@88599 268f45cc-cd09-0410-ab3c-d52691b4dbfc