Reviewed by Eric Carlson.

        Updating 17 media layout tests to provide different media files based on supported codecs.

        https://bugs.webkit.org/show_bug.cgi?id=29625

        * media/audio-constructor-autobuffer.html: Switched to findMediaFile().
        * media/audio-constructor-src.html: Ditto.
        * media/audio-constructor.html: Ditto.
        * media/audio-controls-rendering.html: Ditto.
        * media/audio-delete-while-slider-thumb-clicked.html: Ditto.
        * media/audio-delete-while-step-button-clicked.html: Ditto.
        * media/broken-video.html: Ditto.
        * media/controls-after-reload.html: Ditto, and also changed initial video to counting.mp4 since scaled-matrix.mov is QuickTime specific.
        * media/controls-right-click-on-timebar.html: Ditto.
        * media/event-attributes.html: Ditto.
        * media/media-load-event.html: Ditto.
        * media/media-startTime.html: Ditto.
        * media/progress-event-total-expected.txt: Added new total value.
        * media/progress-event-total.html: Switched to for loop and findMediaFile(), added new total value.
        * media/progress-event.html: Switched to findMediaFile().
        * media/remove-from-document-no-load.html: Ditto.
        * media/remove-from-document.html: Ditto.
        * media/unsupported-tracks.html: Ditto.

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@48694 268f45cc-cd09-0410-ab3c-d52691b4dbfc