Revert of Replace scoped_ptr with unique_ptr in webrtc/common_audio/

webrtc/common_audio/fir_filter_neon.h

Index: webrtc/common_audio/fir_filter_neon.h
diff --git a/webrtc/common_audio/fir_filter_neon.h b/webrtc/common_audio/fir_filter_neon.h
index 5576856b72ca8d11ceb5232d7879f2efde61c2c2..3aa6168dd276425bdbba7d15f4f3c31ab8d279bf 100644
--- a/webrtc/common_audio/fir_filter_neon.h
+++ b/webrtc/common_audio/fir_filter_neon.h
@@ -11,8 +11,7 @@
 #ifndef WEBRTC_COMMON_AUDIO_FIR_FILTER_NEON_H_
 #define WEBRTC_COMMON_AUDIO_FIR_FILTER_NEON_H_
 
-#include <memory>
-
+#include "webrtc/base/scoped_ptr.h"
 #include "webrtc/common_audio/fir_filter.h"
 #include "webrtc/system_wrappers/include/aligned_malloc.h"
 
@@ -29,8 +28,8 @@
  private:
   size_t coefficients_length_;
   size_t state_length_;
-  std::unique_ptr<float[], AlignedFreeDeleter> coefficients_;
-  std::unique_ptr<float[], AlignedFreeDeleter> state_;
+  rtc::scoped_ptr<float[], AlignedFreeDeleter> coefficients_;
+  rtc::scoped_ptr<float[], AlignedFreeDeleter> state_;
 };
 
 }  // namespace webrtc