h264parser: Should add a "unsupported" return value
@ndufresne
Submitted by Nicolas Dufresne Link to original bug (#797217)
Description
Currently, our parser will return "broken data" whenever an unsupported type is met. In some cases this is the correct thing to do, as it's forbidden by the spec, but in other case, this leads to data being dropped as if it was broken.
My suggestion would be to introduce an "unsupported" return value. This way, parser element can simply pass-through these NALs, as they are not proven to be invalid. This applies to non MVC slice entension types, for which we have a hack in h264parse element to avoid dropping.