Replace scoped_ptr with std::unique_ptr in //media/base.

media/base/video_frame_metadata.cc

Index: media/base/video_frame_metadata.cc
diff --git a/media/base/video_frame_metadata.cc b/media/base/video_frame_metadata.cc
index 6aa322669c822cbcc5b88a7ca57b31319fe2b385..1fcba0f3adf8168783392331557a904c16930a93 100644
--- a/media/base/video_frame_metadata.cc
+++ b/media/base/video_frame_metadata.cc
@@ -73,7 +73,7 @@ void VideoFrameMetadata::SetTimeTicks(Key key, const base::TimeTicks& value) {
   SetTimeValue(key, value, &dictionary_);
 }
 
-void VideoFrameMetadata::SetValue(Key key, scoped_ptr<base::Value> value) {
+void VideoFrameMetadata::SetValue(Key key, std::unique_ptr<base::Value> value) {
   dictionary_.SetWithoutPathExpansion(ToInternalKey(key), std::move(value));
 }