Revert of Implement software fallback for PPB_VideoDecoder. (https://codereview.chrom...

Revert of Implement software fallback for PPB_VideoDecoder. (https://codereview.chromium.org/311853005/)

Reason for revert:
Broke blink Linux tests compile.http://build.chromium.org/p/chromium.webkit/builders/Linux%20Tests/builds/37259

Original issue's description:
> Implement software fallback for PPB_VideoDecoder.
> This modifies the proxy to implement software fallback mode.
> The main change is to the host, which now can work with
> media::VideoDecoders.
>
> media::VideoDecoder works differently from media::VideoDecodeAccelerator
> so an adapter object, content::VideoDecoderShim is defined. It lives on the main thread and drives the actual decoder on the media thread via a child DecoderImpl class, which sends back frames of video. VideoDecoderShim receives those and converts frames to GL textures.
>
> gpu::Mailboxes are used so the host can create textures that are aliased
> to the plugin's textures.
>
> The test plugin has been changed to include bitstream data for VP8 in order to
> test the software decoder. The data is in ppapi/examples/video_decode/testdata.h
> alongside the H264 data. The file diff is too large for this site but is structured
> something like this:
>
> const unsigned char kData[] = {
> #if defined USE_VP8_TESTDATA_INSTEAD_OF_H264
> ...  lots of VP8 data
>
> #else  // !USE_VP8_TESTDATA_INSTEAD_OF_H264
> ...  lots of H264 data
>
> #endif  // USE_VP8_TESTDATA_INSTEAD_OF_H264
> };
>
>
> There is a TODO to convert the example to load a file. I'm not sure how to go
> about that but am willing to do the work if someone can point the way.
>
> BUG=281689
> R=dmichael@chromium.org, fischman@chromium.org, sievers@chromium.org, tsepez@chromium.org
>
> Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=277012

TBR=dmichael@chromium.org,fischman@chromium.org,igorc@chromium.org,piman@chromium.org,sievers@chromium.org,tsepez@chromium.org,bbudge@chromium.org
NOTREECHECKS=true
NOTRY=true
BUG=281689

Review URL: https://codereview.chromium.org/337683002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@277015 0039d316-1c4b-4281-b951-d872f2087c98