Renames FilterMode to FilterModeEnum for compatibility
with google3 libyuv

Change-Id: Iec845e6a6aeac4171790c87ce3dd9000ab840a36

This commit enables a background detection approach for adaptive
quantizer control. It combines the cyclic refresh pattern and the
background information to determine the segment id for adaptive
quantizer selection, prior to the non-RD mode decision process.
It hence allows proper quantization information update for a more
precise rate-distortion modeling in the non-RD mode decision.

The compression performance of speed -5 for rtc set is improved
by 2.5%, at no speed change.

Change-Id: Ic3713e8ed9185b403b5b1679d19dabd57506d452

lost in the shuffle of:
4fd63175 Remove duplicate code in test/webm_video_source.h

Change-Id: I89792fa17f03920616c55486bbdaf56c6461c9eb

Change-Id: I35f948fe1ac107950c8d8e4ba06e5a95ac4ec30e

Change-Id: I802308de4817e48a627bb44a744d32010fe7818f

Change-Id: Ifd008968326e61ab492162351e358bf0ac0dac0a

Change-Id: I983364b33e8f103b43a0448821e890989176f1cc

The right value is calculated and set in vp9_pick_filter_level().

Change-Id: I5f725ac21f90dc9b80181a09a2040970bf6671d4

Change-Id: Id48edd12c6f649c82113128491ef6ea7410e93b2

Change-Id: I922d988486b47f413d11a8eeb38532a484d15c80

Remove duplicate WebM parsing code in test/webm_video_source.h and linking it
against webmdec.c which does the exact same thing.

Change-Id: Ib7152eecde890fca58be42028cab18c9cb54221c

Remove call to warn() in webmdec.c so that it does not depend on
tools_common.c for compilation.

Change-Id: I2790e837985ce1d84b35f5a20c783d0e6020a9f5

Use the correct buffer to update the coding mode decision for
sub8x8 blocks.

Change-Id: I091ef27d2047eeb8b73ceb7c2c7c45b38ba8c6d5

Change-Id: I43de248615b79828d5164b670e7358b8a520d075

Change-Id: Idca7c1cd8a12df465c58b6ba064a99404b3b4bce

Use cq_level (which is identical) from VP9_CONFIG instead.

Change-Id: I1aaf2fcef3d2dbd4577f613d27693ff8a68989fd

Change-Id: I2d577d11966fcc5ffaaf0896bf51d18078ad1e9c

To make direct side by side testing this patch combines two
VBR corrections schemes to allow more direct side by side testing.
(The other patch was by Debargha chg id I0cd1f7...)

Change-Id: I271c45e5c4ccf8de8305589000218b80d9dc3a25