Bug 863224. DOMMediaStream should release its internal MediaStream and listener during Unlink to ensure that events running between Unlink and the destruction of the DOMMediaStream don't see the dying object. r=jesup

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extra : rebase_source : 8937bb0d3aa182bc548b193151d51be80c4a80b2
Bug 866514. Part 1: Add DOMMediaStream::OnTracksAvailableCallback. r=jesup

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extra : rebase_source : 8d8da0bc2a55fa14f837cb85f35236ca33d2437d
Bug 866514. Part 2: Delay delivering getUserMedia stream result until the DOM object has asynchronously acquired the desired tracks. r=jesup

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extra : rebase_source : 26a908d2e1bcf0d6d83a864f47dd9d117699bb9c
Bug 866579. Don't bother adding an arena-allocated DisplayItemClip to mDisplayItemClipsToDestroy if its destructor isn't going to do anything interesting. r=mattwoodrow

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extra : rebase_source : b8b64d9697cd2f19a42ff751cbfb7a1566f28209
Bug 868406. Shut down MediaStreamGraph's thread. r=jesup

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extra : rebase_source : 0d5801b271d1658dba172cb5b156186052651990