Revert of Add accelerated VP9 decode infrastructure and an implementation for VA-API. (patchset #7 id:260001 of https://codereview.chromium.org/1318863003/ )

Reason for revert:
I think this patch broke compile step for Chromium Linux ChromeOS MSan Builder.

First failing build:
http://build.chromium.org/p/chromium.memory.fyi/builders/Chromium%20Linux%20ChromeOS%20MSan%20Builder/builds/8310

All recent builds:
http://build.chromium.org/p/chromium.memory.fyi/builders/Chromium%20Linux%20ChromeOS%20MSan%20Builder?numbuilds=200

Sorry for the revert. I'll re-revert if I'm wrong.

Cheers,

Tommy

Original issue's description:
> Add accelerated VP9 decode infrastructure and an implementation for VA-API.
>
> - Add a hardware/platform-independent VP9Decoder class and related
> infrastructure, implementing AcceleratedVideoDecoder interface. VP9Decoder
> performs the initial stages of the decode process, which are to be done
> on host/in software, such as stream parsing and reference frame management.
>
> - Add a VP9Accelerator interface, used by the VP9Decoder to offload the
> remaining stages of the decode process to hardware. VP9Accelerator
> implementations are platform-specific.
>
> - Add the first implementation of VP9Accelerator - VaapiVP9Accelerator - and
> integrate it with VaapiVideoDecodeAccelerator, for devices which provide
> hardware VP9 acceleration through VA-API. Hook it up to the new
> infrastructure and VP9Decoder.
>
> - Extend Vp9Parser to provide functionality required by VP9Decoder and
> VP9Accelerator, including superframe parsing, handling of loop filter
> and segmentation initialization, state persistence across frames and
> resetting when needed. Also add code calculating segmentation dequants
> and loop filter levels.
>
> - Update vp9_parser_unittest to the new Vp9Parser interface and flow.
>
> TEST=vp9_parser_unittest,vda_unittest,Chrome VP9 playback
> BUG=chrome-os-partner:41469,chrome-os-partner:41470,chromium:525331
> TBR=dpranke@chromium.org
>
> Committed: https://crrev.com/e3cc0a661b8abfdc74f569940949bc1f336ece40
> Cr-Commit-Position: refs/heads/master@{#349312}

TBR=wuchengli@chromium.org,kcwu@chromium.org,sandersd@chromium.org,jorgelo@chromium.org,posciak@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=chrome-os-partner:41469,chrome-os-partner:41470,chromium:525331

Review URL: https://codereview.chromium.org/1357513002

Cr-Commit-Position: refs/heads/master@{#349443}
inline bool IsChromeOS() {
#if defined(OS_CHROMEOS)
  return true;
#else
  return false;
#endif
}

inline bool IsChromeOS() {
#if defined(OS_CHROMEOS)
  return true;
#else
  return false;
#endif
}
