ext/ffmpeg/gstffmpegdec.c: If we have a parser and we did not consume any of the...

ext/ffmpeg/gstffmpegdec.c: If we have a parser and we did not consume any of the bytes of a new buffer, make sure we ...

Original commit message from CVS:
* ext/ffmpeg/gstffmpegdec.c: (gst_ffmpegdec_frame),
(gst_ffmpegdec_chain):
If we have a parser and we did not consume any of the bytes of a new
buffer, make sure we submit the buffer again with its original timestamp
instead of a -1 timestamp. Fixes various h264 cases with reordered
frames.
If we have a discont and a timestamp but the first buffer after the
discont did not produce any data, make sure we set the timestamp on the
next buffer instead. Fixes initial timestamp on realaudio in many cases.