Support VP9 video in the BT709 color space.

media/filters/vpx_video_decoder.cc

Index: media/filters/vpx_video_decoder.cc
diff --git a/media/filters/vpx_video_decoder.cc b/media/filters/vpx_video_decoder.cc
index dd436796ce1c20500cc5dc38f251fb0b81b9caac..f67c4226df02443ea8ceded99238318e5e38b479 100644
--- a/media/filters/vpx_video_decoder.cc
+++ b/media/filters/vpx_video_decoder.cc
@@ -466,6 +466,11 @@ void VpxVideoDecoder::CopyVpxImageTo(const vpx_image* vpx_image,
     uv_rows = vpx_image->d_h;
   } else if (vpx_codec_alpha_) {
     codec_format = VideoFrame::YV12A;
+  } else if (vpx_image->cs == VPX_CS_BT_709) {
+    // TODO(watk): A limitation of conflating color space with pixel format is
+    // that it's not possible to have BT709 with alpha.
+    // Until color space is separated from format, prefer YV12A over YV12HD.

[xhwang, 2015/03/04 18:07:14]

This seems more like a comment/todo for l.468. Move it up a bit?

[watk, 2015/03/04 18:23:02]

Done.

+    codec_format = VideoFrame::YV12HD;
   }
 
   gfx::Size size(vpx_image->d_w, vpx_image->d_h);