[Mac] allow host application to canonicalize media urls
https://bugs.webkit.org/show_bug.cgi?id=134329

Reviewed by Dean Jackson.

* platform/graphics/avfoundation/objc/MediaPlayerPrivateAVFoundationObjC.mm:
(WebCore::canonicalURL): New, use NSURLProtocol to canonicalize a URL.
(WebCore::MediaPlayerPrivateAVFoundationObjC::createAVAssetForURL): Call canonicalURL.


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@170478 268f45cc-cd09-0410-ab3c-d52691b4dbfc