Revert of Replace scoped_ptr with unique_ptr in webrtc/common_audio/

webrtc/common_audio/sparse_fir_filter_unittest.cc

Index: webrtc/common_audio/sparse_fir_filter_unittest.cc
diff --git a/webrtc/common_audio/sparse_fir_filter_unittest.cc b/webrtc/common_audio/sparse_fir_filter_unittest.cc
index 21b28ed34acb02ba5ac93c949e936c3acd189025..82a53a52879a43a29c6ba50c390ef65bbc8bc78a 100644
--- a/webrtc/common_audio/sparse_fir_filter_unittest.cc
+++ b/webrtc/common_audio/sparse_fir_filter_unittest.cc
@@ -8,12 +8,11 @@
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
-#include <memory>
-
 #include "webrtc/common_audio/sparse_fir_filter.h"
 
 #include "testing/gtest/include/gtest/gtest.h"
 #include "webrtc/base/arraysize.h"
+#include "webrtc/base/scoped_ptr.h"
 #include "webrtc/common_audio/fir_filter.h"
 
 namespace webrtc {
@@ -215,8 +214,9 @@
   const size_t kOffset = 0;
   float output[arraysize(kInput)];
   float sparse_output[arraysize(kInput)];
-  std::unique_ptr<FIRFilter> filter(
-      FIRFilter::Create(kCoeffs, arraysize(kCoeffs), arraysize(kInput)));
+  rtc::scoped_ptr<FIRFilter> filter(FIRFilter::Create(kCoeffs,
+                                                      arraysize(kCoeffs),
+                                                      arraysize(kInput)));
   SparseFIRFilter sparse_filter(kCoeffs,
                                 arraysize(kCoeffs),
                                 kSparsity,