Bug 1208371 - Add a PrincipalIdListener to MediaStreamTrack. r?roc,mt

Bug 1208371 - Add `NotifyPrincipalIdChange` to MediaStreamTrackListener. r?mt,roc

Bug 1208371 - Add PrincipalID to MediaChunks. r?mt,roc PrincipalID is a void pointer that can be passed by value in the MSG. A MediaStreamTrack whose source has just updated its principal, sets the new principal aside (as its "pending principal"), and combines the new principal into its current principal. Then the source starts passing the new principal to the MediaStreamGraph as a PrincipalID (the nsIPrincipal is static_cast()ed). Changes to a track's PrincipalID on the MSG will be surfaced through the MediaStreamTrackListener API. These changes are dispatched to main thread and compared to a MediaStreamTrack's pending principal. In case of a match the track knows the correct principal is flowing and can move the pending principal to the current principal and update any main thread principal observers.

testAssert

Bug 1208371 - Forward declare DOMMediaStream in HTMLMediaElement.h. r?roc

Bug 1208371 - Forward declare MediaStreamGraph classes in MediaPipeline.h. r?bwc

Bug 1208371 - Move GetCurrentTime undef to DOMMediaStream.cpp. r?jesup Not sure why this surfaced now. Include ordering must have changed.

Bug 1208371 - Move MediaStreamTrack's label to MediaStreamTrackSource. r?jib

Bug 1208371 - Clean up unnecessary virtuals in MediaPipeline. r?bwc

Bug 1208371 - Forward declare MediaStreamTrack in MediaPipeline.h. r?bwc

Bug 1208371 - Ensure a media element's ImageContainer is protected when playing a stream. r?mt,roc HTMLMediaElement needs special protection when playing a stream since its ImageContainer can outlive the video track of a stream. Consider for instance when a (cross-origin) video track is removed from a DOMMediaStream by a user and the remaining video track (non-CORS) does not yet contain any actual video frames. The HTMLMediaElement will display a frame from the removed track but the DOMMediaStream's principal has been updated to not include the principal from the removed track. With this patch we handle this by letting VideoFrameContainer notify HTMLMediaElement when it has flushed out all video frames belonging to a certain principalId. I.e., when a new principalId has been applied to the underlying ImageContainer.

Bug 1208371 - Ensure DOMMediaStream principals reflect what could reside in their playback streams. r?mt,roc Calculating a principal when adding a track is easy - just combine the new track principal into the stream's principal. When removing a track it's a bit trickier. The DOMMediaStream has to wait until the MediaStreamGraph has removed the track from the underlying playback stream. We do this by letting the MediaStreamGraph return a Pledge (single threaded Promise) when blocking a track in a stream (the way we end removed tracks). The pledge gets passed to the MediaStreamGraph and when the block has been applied it is passed back to the main thread where it is finally resolved and the DOMMediaStream may recompute its principal once all outstanding track removals have been applied.

Bug 1208371 - Hook up MediaPipeline with principalId. r?mt,bwc

Bug 1208371 - Hook up DecodedStream with principalId. r?mt,jwwang

Bug 1208371 - Add a PrincipalIdListener to MediaStreamTrack. r?roc,mt

Bug 1208371 - Add `NotifyPrincipalIdChange` to MediaStreamTrackListener. r?mt,roc

Bug 1208371 - Add PrincipalID to MediaChunks. r?mt,roc PrincipalID is a void pointer that can be passed by value in the MSG. A MediaStreamTrack whose source has just updated its principal, sets the new principal aside (as its "pending principal"), and combines the new principal into its current principal. Then the source starts passing the new principal to the MediaStreamGraph as a PrincipalID (the nsIPrincipal is static_cast()ed). Changes to a track's PrincipalID on the MSG will be surfaced through the MediaStreamTrackListener API. These changes are dispatched to main thread and compared to a MediaStreamTrack's pending principal. In case of a match the track knows the correct principal is flowing and can move the pending principal to the current principal and update any main thread principal observers.

Bug 1208371 - Move FindTrack from SourceMediaStream to MediaStream. r?roc

Bug 1208371 - Ensure that MediaManager ends all tracks before finishing its source stream. r?jib This puts all the logic in GetUserMediaCallbackMediaStreamListener and none in MediaOperationTask to make it simpler to reason about what's happening. When we want to stop a track, the gUMCallbackListener will send a MEDIA_STOP_TRACK if other tracks will still be live. If it was the last live track, the gUMCallbackListener will send a MEDIA_STOP instead. The MEDIA_STOP makes sure the passed in devices (we pass in all) are stopped before finishing the stream.

Bug 1208371 - Assert when stream finishes but contains live tracks. r?roc This was the cause of some intermittent assertion failures, as the non-ended track didn't contain enough data when linked to other streams in the graph, but input extraction wouldn't get that data since the stream was finished.