Convert //media/audio from scoped_ptr to std::unique_ptr

media/audio/cras/cras_unified.h

Index: media/audio/cras/cras_unified.h
diff --git a/media/audio/cras/cras_unified.h b/media/audio/cras/cras_unified.h
index cb6164714d059b61df07e7019f2ec7cdd57a5dc0..b9fcaa5df91f26936f1527007407dedac9026db3 100644
--- a/media/audio/cras/cras_unified.h
+++ b/media/audio/cras/cras_unified.h
@@ -14,6 +14,8 @@
 #include <stddef.h>
 #include <stdint.h>
 
+#include <memory>
+
 #include "base/compiler_specific.h"
 #include "base/macros.h"
 #include "media/audio/audio_io.h"
@@ -106,7 +108,7 @@ class MEDIA_EXPORT CrasUnifiedStream : public AudioOutputStream {
   AudioSourceCallback* source_callback_;
 
   // Container for exchanging data with AudioSourceCallback::OnMoreData().
-  scoped_ptr<AudioBus> output_bus_;
+  std::unique_ptr<AudioBus> output_bus_;
 
   // Direciton of the stream.
   CRAS_STREAM_DIRECTION stream_direction_;