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

media/audio/mac/audio_auhal_mac.h

Index: media/audio/mac/audio_auhal_mac.h
diff --git a/media/audio/mac/audio_auhal_mac.h b/media/audio/mac/audio_auhal_mac.h
index 7d7f606585701eda6cbd7f83d0e9b492950723ff..b4fce5d708e8b729a23ba7d11f2dd15efde8b432 100644
--- a/media/audio/mac/audio_auhal_mac.h
+++ b/media/audio/mac/audio_auhal_mac.h
@@ -22,6 +22,8 @@
 #include <stddef.h>
 #include <stdint.h>
 
+#include <memory>
+
 #include "base/cancelable_callback.h"
 #include "base/compiler_specific.h"
 #include "base/macros.h"
@@ -178,11 +180,11 @@ class AUHALStream : public AudioOutputStream {
   bool stopped_;
 
   // Container for retrieving data from AudioSourceCallback::OnMoreData().
-  scoped_ptr<AudioBus> output_bus_;
+  std::unique_ptr<AudioBus> output_bus_;
 
   // Dynamically allocated FIFO used when CoreAudio asks for unexpected frame
   // sizes.
-  scoped_ptr<AudioPullFifo> audio_fifo_;
+  std::unique_ptr<AudioPullFifo> audio_fifo_;
 
   // Current buffer delay.  Set by Render().
   uint32_t current_hardware_pending_bytes_;