Pass direct Core::EventLoop references through media producer and
playback plumbing that posts work back to the main thread. The browser
process main loops stay alive for the process lifetime, so these paths
no longer need weak event loop references.
Update LibMedia tests to pass their stack event loop directly to the
producer helpers.
Seeks don't always move a decoded data producer's head, so we need to
make sure not to remove queued data downstream when that is the case.
To communicate this, the producers can now be queried before pulling
data, allowing them to have an in-band signal to clear the queued data
after a seek has moved the producer and broken monotonicity.
This fixes a flake in HTMLVideoElement-resize-event-during-playback.
Previously, we weren't too consistent about the definition of frame and
sample when it relates to raw audio data. This brings all the usages in
the context of raw data in line (hopefully), with samples referring to
a single PCM value, and frames referring to the multiple samples that
make up an instant's audio across all channels.
This is an intermediate step towards unifying the pipeline around new
Producer/Sink interfaces. Producers now have a pull() method that gets
the next piece of data from them. The pull() method returns a status
that can indicate whether it has current data, and if not, why it's
unavailable. This signal will be passed down the pipeline to the final
sink, which can expose the signal to its user, which in the normal
playback pipeline is PlaybackManager. The signal can be used to
transition between playback states. Currently, this is only hooked up
to the buffering state, but should be used later for ending playback
as well as decoding error propagation.
Buffering is now determined solely based on whether the pipeline is
blocked on incomplete data, so the ready state for video now progresses
past HAVE_METADATA immediately after playback manager initializes. This
will change when files have buffered ranges.
- Provider -> producer
- (Audio|Video)DataProvider -> Decoded(Audio|Video)Producer
- MediaTimeProvider remains suffixed Provider, moves out of the
Providers folder to the root of LibMedia
This brings the naming more in line with the intended split
functionality split between different nodes in the pipeline.
Apparently this function uses a bitrate heuristic to determine which
track is best. We don't want or need that, so just select the first
track with default disposition (e.g. FlagDefault=1 in Matroska).
