Revert of Replace scoped_ptr with unique_ptr in webrtc/common_audio/

webrtc/common_audio/blocker.h

Index: webrtc/common_audio/blocker.h
diff --git a/webrtc/common_audio/blocker.h b/webrtc/common_audio/blocker.h
index edf81d337a5a8ff9dddbaa009a8ba74d0f8c5088..3a67c134d0a67287d6824681c493634a3bc4864b 100644
--- a/webrtc/common_audio/blocker.h
+++ b/webrtc/common_audio/blocker.h
@@ -11,8 +11,7 @@
 #ifndef WEBRTC_INTERNAL_BEAMFORMER_BLOCKER_H_
 #define WEBRTC_INTERNAL_BEAMFORMER_BLOCKER_H_
 
-#include <memory>
-
+#include "webrtc/base/scoped_ptr.h"
 #include "webrtc/common_audio/audio_ring_buffer.h"
 #include "webrtc/common_audio/channel_buffer.h"
 
@@ -110,7 +109,7 @@
   // Space for the output block (can't wrap because of overlap/add).
   ChannelBuffer<float> output_block_;
 
-  std::unique_ptr<float[]> window_;
+  rtc::scoped_ptr<float[]> window_;
 
   // The amount of frames between the start of contiguous blocks. For example,
   // |shift_amount_| = |block_size_| / 2 for a Hann window.