https://bugs.webkit.org/show_bug.cgi?id=75192

https://bugs.webkit.org/show_bug.cgi?id=75192

Reviewed by Darin Adler.

Notify the media element when tracks are added to and removed from a document instead of
a tree because we don't want to trigger loading unless a track element is in the document.

Test: media/track/track-delete-during-setup.html

* html/HTMLMediaElement.cpp:
(WebCore::HTMLMediaElement::trackWasRemoved): Renamed from trackWillBeRemoved because it is
    now called after removal.
* html/HTMLMediaElement.h:

* html/HTMLTrackElement.cpp:
(WebCore::HTMLTrackElement::insertedIntoDocument): Was insertedIntoTree. Use this instead
    because we care about when a track is inserted and removed from a document, not a tree.
(WebCore::HTMLTrackElement::removedFromDocument): Ditto.
* html/HTMLTrackElement.h:

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@105434 268f45cc-cd09-0410-ab3c-d52691b4dbfc