mxfdec: set extradata size

The line setting it was mistakenly removed in
ecf442a58b09bdb1dc1d2c3904b82ac5f79b2878
mpeg4videodec: add a mpeg4-specific private context.
mpeg4videodec: move MpegEncContext.shape to Mpeg4DecContext
mpeg4videodec: move MpegEncContext.time_increment_bits to Mpeg4DecContext

The field remains in MpegEncContext for use in the encoder.
mpeg4videoenc: write 0 instead of vol_sprite_usage

That field is never set for encoding.
mpeg4videodec: move MpegEncContext.vol_sprite_usage to Mpeg4DecContext
mpeg4videodec: remove write-only sprite variables from MpegEncContext
mpeg4videodec: move MpegEncContext.rvlc to Mpeg4DecContext
h263dec: remove commented out cruft
mpeg4videoenc: don't set MpegEncContext.resync_marker

It is only used in one place immediately after it is set.
vc1: move MpegEncContext.resync_marker into VC1Context.

The field still remains in MpegEncContext because it is used by the
mpeg4 decoder.
mpeg4videodec: move MpegEncContext.resync_marker into Mpeg4DecContext.
Merge commit '95fd52c11bff1aad93a29aed3bd5472bd2981d1f'

* commit '95fd52c11bff1aad93a29aed3bd5472bd2981d1f':
  mxfdec: set extradata size

Conflicts:
	libavformat/mxfdec.c

no change as ffmpeg was not affected by this bug

Merged-by: Michael Niedermayer <michaelni@gmx.at>
Merge commit '35e0833d410e31d9fd35695ad798c5d13de2af58'

* commit '35e0833d410e31d9fd35695ad798c5d13de2af58':
  mpeg4videodec: add a mpeg4-specific private context.

Conflicts:
	libavcodec/mpeg4video_parser.c
	libavcodec/mpeg4videodec.c

Merged-by: Michael Niedermayer <michaelni@gmx.at>
Merge commit 'ee8af2dd99dcb7a01a667deedec81d1aa2a00d72'

* commit 'ee8af2dd99dcb7a01a667deedec81d1aa2a00d72':
  mpeg4videodec: move MpegEncContext.shape to Mpeg4DecContext

Conflicts:
	libavcodec/h263dec.c
	libavcodec/mpeg4videodec.c

Merged-by: Michael Niedermayer <michaelni@gmx.at>
Merge commit 'e62a43f6b1a9c0c82e1df33c0c038e32029c0aa4'

* commit 'e62a43f6b1a9c0c82e1df33c0c038e32029c0aa4':
  mpeg4videodec: move MpegEncContext.time_increment_bits to Mpeg4DecContext

Conflicts:
	libavcodec/mpeg4videodec.c

Merged-by: Michael Niedermayer <michaelni@gmx.at>
Merge commit '75bd07f732fb575c2b88dc7cd08a6bb12c2e24ea'

* commit '75bd07f732fb575c2b88dc7cd08a6bb12c2e24ea':
  mpeg4videoenc: write 0 instead of vol_sprite_usage

Merged-by: Michael Niedermayer <michaelni@gmx.at>
Merge commit '1a89025793ca73d9685a8ce8e3194efa64dd6844'

* commit '1a89025793ca73d9685a8ce8e3194efa64dd6844':
  mpeg4videodec: move MpegEncContext.vol_sprite_usage to Mpeg4DecContext

Merged-by: Michael Niedermayer <michaelni@gmx.at>
avcodec/mpeg4videodec: Fix code so it also works after moving vol_sprite_usage around

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
Merge commit '9f0617d2137bb7231b181d74392cd84ef4844cd7'

* commit '9f0617d2137bb7231b181d74392cd84ef4844cd7':
  mpeg4videodec: remove write-only sprite variables from MpegEncContext

Merged-by: Michael Niedermayer <michaelni@gmx.at>