This tests that SourceBuffer deals with swapping audio/video track IDs properly (should not crash).

RUN(video.src = URL.createObjectURL(source))
EVENT(sourceopen)
RUN(sourceBuffer = source.addSourceBuffer(loader.type()))
Append an initialization segment.
RUN(sourceBuffer.appendBuffer(loader.initSegment()))
EVENT(update)
Append a media segment.
RUN(sourceBuffer.appendBuffer(loader.mediaSegment(0)))
EVENT(update)
Append a media segment.
RUN(sourceBuffer.appendBuffer(loader.mediaSegment(1)))
EVENT(update)

Append another initialization segment with audi/video track IDs swapped.
RUN(sourceBuffer.appendBuffer(loader.initSegment()))
EVENT(update)
Append a media segment.
RUN(sourceBuffer.appendBuffer(loader.mediaSegment(0)))
EVENT(update)
END OF TEST