SDK / exoplayer

Adds a method to FrameProcessor.Listener to be called when an
output frame is available and a method releaseOutputFrame in
FrameProcessor allowing the caller to trigger release of the
oldest available output frame at a given timestamp. Late frames
or frames with unset release times are dropped in the
FinalMatrixTransformationProcessorWrapper.

More than one output frame can become available before they are
released if the penultimate GlTextureProcessor is capable of producing
multiple output frames. Processing continues while waiting for
releaseOutputFrame to be called. Frame release tasks are prioritized
over other tasks.

PiperOrigin-RevId: 468473072
(cherry picked from commit 2c063546)