The implicitly changed value would be used for contextualizing future
skip flags of neighbour blocks (bottom/right), which is certainly not
what was intended. The original code stems from vp8, and was useful
in cases where coding of the skip flag was disabled. In vp9, the skip
flag is always coded. The result of this change is that for bitstream
parsing purposes, decoding of the skip flag becomes independent of
decoding of block coefficients.
See issue 1014.
Change-Id: I8629e6abe76f7c1d649f28cd6fe22a675ce4a15d
See issue 1030. The value of frame_parallel_decoding_mode was ignored
in vp9 if refresh_frame_context was 0, so instead make it a 3-member
enum where the dependency is obviously stated.
Change-Id: I37f0177e5759f54e2e6cc6217023d5681de92438
