In upstream bug 9106 they removed FrameBuffer::Start, making VideoReceiveStream::Stop final. After such a Stop, VideoReceiveStream::Start would not again start the FrameBuffer, so once that happens the FrameBuffer ends up blocking any received frames from being decoded.
Best would be to rework the Transceiver so that we never have to restart the receive stream. Should we still need to restart it we'd have to recreate it. All the implications of that I'm not sure of, but for one we'd drop all the frames currently waiting in the jitter buffer (aka FrameBuffer).
Possibly we could undelete FrameBuffer::Start but one would assume it was removed for good reasons.