Basic assumption: when talking about transform units, use b_; when
talking about macroblock indices, use mb_.

Change-Id: Ifd163f595d4924ff892de4eb0401ccd56dc81884

The quantizer can vary per-plane, and the dequantization vector is
available in the per-plane part of MACROBLOCKD. The previous code would
incorrectly use the Y quantizer for the whole macroblock.

Change-Id: I3ab418aef9168ea0ddcfa4b7c0be32ae48b536d7

Access these members from MACROBLOCKD instead.

Change-Id: I2574622e577bb9feede47f6b7ccbb11f3e928ca8

The underlying storage for these buffers is in the per-plane MACROBLOCKD
area, so read it from there directly.

Change-Id: Id6bd835117fdd9dea07db95ad06eff9f12afaaf7

This data can vary per-plane, but not per-block.

Change-Id: I1971b0b2c2e697d2118e38b54ef446e52f63c65a

All members can be referenced from their per-plane counterparts, and
removes assumptions about 24 blocks per macroblock.

Change-Id: I593fb0715e74cd84b48facd1c9b18c3ae1185d4b

Change-Id: I2d32d46002cb92c63050c2b8328865c406103621

Using ALLOWED_REFS_PER_FRAME constants instead of hard coded 3, replacing
memcpy with plain struct assignment.

Change-Id: Ibc86f5d175fcb3f3a3eddacf593525370f1f854c

Function set_mb_row() and set_mb_col() do similar work and are always
called together, this commit merged them into a single function for
clarity and easy maintainence.  This was a TODO item.

Change-Id: I956bd9ed6afb8b2b0469b20fd8bc893b26f8a0f3

Move rectangular superblock coding out of experimental list.

Change-Id: I96c37547d122330d666a67b4bf577ae54547857f

This commit enables selecting probability models for recursive block
partition information syntax, depending on its above/left partition
information, as well as the current block size. These conditional
probability models are reasonably stationary and consistent across
frames, hence the backward adaptive approach is used to maintain and
update the contextual models.

It achieves coding performance gains (on top of enabling rectangular
block sizes):
derf:   0.242%
yt:     0.391%
hd:     0.376%
stdhd:  0.645%

Change-Id: Ie513d9673337f0d27abd65fb566b711d0844ec2e

Change-Id: Icb671cd011f645a3361684207840d14330ca7488

Adding xd->up_available as additional check for above context.

Change-Id: If5654e4cae184b9c369b7b2e08076cb2951d00ed

Change-Id: I6ea9e110b5c5b07ab7d092886dbd51a6eccc0217

Also some further simplification following removal
of top node code.

There is an issue in regards to the shared file vp8cx.h
in regard to the roi_map as this interface assumes that
there are only 4 segments. I have left the value here as
4 for now meaning that the roi_map interface is broken
for VP9.

Note that this change would have been easier if I hadn't
had to search for hard wire instances of the number 4
and <= 3.

Change-Id: Ia8b6deea4be4dbd20deb1656e689dd43a5f190e8

Remove top node optimization.
The improvement this gives is not sufficient to justify
the extra complexity.

Change-Id: I2bb4a12a50ffd52cacfa4a3e8acbb2e522066905

Change-Id: Iaef16122732c2a81e0927f9862b51b68dc788712

This data is fixed at the MB level, so move it to the common part
of MACROBLOCK.

Change-Id: Idd8c87118e501cdf0a202bd84c28b502a8234edf

Quantizers can vary per plane, but not per block. Move these values to
the per-plane part of MACROBLOCK.

Change-Id: I320a55e38b7b28b29aec751a4aca5ccd0c9b9326

Lookup the data per-plane from the MACROBLOCK struct.

Change-Id: I9253c4d3cf886aa9ab4aeab23a2156bfcf994ede