Removing unused get_sbuv_perpixel_variance function, using has_second_ref/
is_inter_block functions, organizing includes.

Change-Id: I016de4af12fbbb8b4ece26a70759b2392651b095

Change-Id: Ieb7077ca3586b9491912027eed450a4f6fd38d30

This commit changes the partition search order of superblocks from
{SPLIT, NONE, HORZ, VERT} to {NONE, SPLIT, HORZ, VERT} for
consistency with that of sub8x8 partition search. It enable the use
of early termination in partition search for all block sizes.

For ped_area_1080p 50 frames coded at 4000 kbps, it makes the runtime
goes down from 844305ms -> 818003ms (3% speed-up) at speed 0.

This will further move towards making the in-search partition types
configurable, hence unifying various speed-up approaches.

Some speed 1 and 2 features are turned off during the refactoring
process, including:
disable_split_var_thresh
using_small_partition_info

Stricter constraints are applied to use_square_partition_only for
right/bottom boundary blocks. Will bring back/refine these features
subsequently. At this point, it makes derf set at speed 1 about
0.45% higher in compression performance, and 9% down in run-time.

Change-Id: I3db9f9d1d1a0d6cbe2e50e49bd9eda1cf705f37c

Adds a couple of minor fixes, which may be absorbed in Jingning's
patch. Thanks to Guillaume for pointing these out.
Also adjusts the thresholds for speed 1 and 2 to 16 and 32
respectively, to keep quality drops small.

Results:
--------
derfraw300:  threshold = 16, psnr -0.082%, speedup 2-3%
             threshold = 32, psnr -0.218%, speedup 5-6%
stdhdraw250: threshold = 16, psnr -0.031%, speedup 2-3%
             threshold = 32, psnr -0.273%, speedup 5-6%

Change-Id: I4b11ae8296cca6c2a9f644be7e40de7c423b8330

It appears that the above/left mb_skip_coeff used during
the pick modes, is left over from the previously
encode frame.  This patch initializes the flag to the default
value of zero.


Change-Id: Ida4684cc99611d6e3e82628db35ed717e28ce550

enable|disable -> (enable|disable)_feature

Change-Id: I7494913c78ebe8bb532fa6545e0ae53a79ccd388

+ disable() -> disable_feature() for balance

this avoids shadowing the bash builtin 'enable' allowing the scripts to
be linted with checkbashisms

Change-Id: Ia11cf86c92ec25bd14e69427b0ac0a9a61a5f7a5

Change-Id: I9f45af3894c57f35cb266c255e2b904295d39c34

currently protected by CONFIG_NON420 as v1 is still not entirely stable

Change-Id: Id1c5081b04a2c47a842822048b8804be67d23a6d

Change-Id: Ib2c975e1d96deefb7ac4d6b600c8c5388035d111

Change-Id: Ib3e72671eb8da6f2e9767a6de292ec7c7cde6bc7

Using size_group_lookup table and better variable names.

Change-Id: I6e67f2ce091845db43ace7d21b7ae31c6f165aec

We can determine plane_type for another function arguments.

Change-Id: I85331877aedb357632ae916a37b5b15f22c0bb1f

Currently, the best quality mode in VP9 is not very well developed,
and unnecessarily makes the encode too slow. Hence the command line
default is changed to "good" quality. Also, the number of passes
default is changed to 2 passes as well, since 1-pass encoding is
not very efficient in VP9.

Besides, a number of VP9 defaults are set to the currently
recommended settings. With these changes, vpxenc
run with --codec=vp9 --kf-max-dist=9999 --cpu-used=0 should
work about the same as our borg results.
Note when the --cpu-used=0 option is dropped there will be a slight
difference in the output, because of a difference in the cpu-used
value for the first pass. Specifically, the default when unspecified
is to use cpu_used=1 for the first pass and cpu_used=0 for the
second pass. But when specified, both passes will use the cpu-used
value specified.

Note that this also changes the default for VP8 as being "good"
but other options stay unchanged.

Change-Id: Ib23c1a05ae2f36ee076c0e34403efbda518c5066

Adding set_contexts contexts function and call it instead of
set_contexts_on_border. Calling txfrm_block_to_raster_xy to get aoff and
loff.

Change-Id: I41897e344afd2cae1f923f4fdbe63daccf6fe80e

We support only [1/16, 2] scale factors, enforcing this now.

Change-Id: I0822eb7cea51720df6814e42d3f35ff340963061

Change-Id: I32e43474e8651ef2eb181d24860a8f118cfea7bf

vp9_sad32x3, vp9_sad3x32

+ remove unnecessary sad include from vp9_findnearmv.c

Change-Id: Idef2a89cadc3fec64eff82ba9be60ffff50b3468

Moving foreach_predicted_block_in_plane function to vp9_reconinter.c
because there is only one usage.

Change-Id: I9852feae43fc3cf809b817fc541d043bc5496209

Updating implementation of vp9_get_pred_context_single_ref_p2 using
has_second_ref function to make code easier to read.

Change-Id: I5ba642712f59861a48aab974e73aa01640d086fe

Change-Id: Ib394ea23f464591dad50b5c65c316701378d06d7