https://bugs.webkit.org/show_bug.cgi?id=108994

Reviewed by Dean Jackson.

Source/WebCore: 

Plumb "isClosedCaptions" through to the Mac media engine.

Updated media/video-controls-captions-trackmenu-localized.html and results.

* html/track/InbandTextTrack.cpp:
(WebCore::InbandTextTrack::isClosedCaptions): New, pass the call through to the private track.
* html/track/InbandTextTrack.h:
(InbandTextTrack):
* html/track/TextTrack.cpp:
(WebCore::TextTrack::TextTrack): Lose the member variable, this won't be accessed often enough
    to make it worth caching the value.
* html/track/TextTrack.h:
(WebCore::TextTrack::isClosedCaptions): Make virtual so derived classes can oveerride.
* platform/graphics/InbandTextTrackPrivate.h:
(WebCore::InbandTextTrackPrivate::isClosedCaptions): New.
* platform/graphics/avfoundation/objc/InbandTextTrackPrivateAVFObjC.h:
* platform/graphics/avfoundation/objc/InbandTextTrackPrivateAVFObjC.mm:
(WebCore::InbandTextTrackPrivateAVFObjC::isClosedCaptions): New.

LayoutTests: 

Update test results now that the Mac media engine identifies CC tracks.

* media/video-controls-captions-trackmenu-localized.html:
* platform/mac/media/video-controls-captions-trackmenu-localized-expected.txt:


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@141957 268f45cc-cd09-0410-ab3c-d52691b4dbfc