Revert of Change the video color space default.

media/filters/ffmpeg_video_decoder.cc

Index: media/filters/ffmpeg_video_decoder.cc
diff --git a/media/filters/ffmpeg_video_decoder.cc b/media/filters/ffmpeg_video_decoder.cc
index 2c604f8226b9570428e950a8d9643de18f78ed96..fdf8dc5841a8085c4831026dd693b6fe3e994acf 100644
--- a/media/filters/ffmpeg_video_decoder.cc
+++ b/media/filters/ffmpeg_video_decoder.cc
@@ -127,15 +127,10 @@
 
   scoped_refptr<VideoFrame> video_frame = frame_pool_.CreateFrame(
       format, coded_size, gfx::Rect(size), natural_size, kNoTimestamp());
-
-  // Prefer the color space from the codec context. If it's not specified (or is
-  // set to an unsupported value), fall back on the value from the config.
-  VideoFrame::ColorSpace color_space =
-      AVColorSpaceToVideoFrameColorSpace(codec_context->colorspace);
-  if (color_space == VideoFrame::COLOR_SPACE_UNSPECIFIED)
-    color_space = config_.color_space();
-  video_frame->metadata()->SetInteger(VideoFrameMetadata::COLOR_SPACE,
-                                      color_space);
+  if (codec_context->colorspace == AVCOL_SPC_BT709) {
+    video_frame->metadata()->SetInteger(VideoFrameMetadata::COLOR_SPACE,
+                                        VideoFrame::COLOR_SPACE_HD_REC709);
+  }
 
   for (int i = 0; i < 3; i++) {
     frame->data[i] = video_frame->data(i);