Replace scoped_ptr with unique_ptr in webrtc/base/

webrtc/base/messagehandler.h

Index: webrtc/base/messagehandler.h
diff --git a/webrtc/base/messagehandler.h b/webrtc/base/messagehandler.h
index b55b229a6db4792dca32ca95c0adaff508c7110d..787aee74c08b3c33672f516c63d864635c4e59cf 100644
--- a/webrtc/base/messagehandler.h
+++ b/webrtc/base/messagehandler.h
@@ -11,6 +11,7 @@
 #ifndef WEBRTC_BASE_MESSAGEHANDLER_H_
 #define WEBRTC_BASE_MESSAGEHANDLER_H_
 
+#include <memory>
 #include <utility>
 
 #include "webrtc/base/constructormagic.h"
@@ -64,6 +65,20 @@ class FunctorMessageHandler<class rtc::scoped_ptr<ReturnT>, FunctorT>
   rtc::scoped_ptr<ReturnT> result_;
 };
 
+// Specialization for std::unique_ptr<ReturnT>.
+template <class ReturnT, class FunctorT>
+class FunctorMessageHandler<class std::unique_ptr<ReturnT>, FunctorT>
+    : public MessageHandler {
+ public:
+  explicit FunctorMessageHandler(const FunctorT& functor) : functor_(functor) {}
+  virtual void OnMessage(Message* msg) { result_ = std::move(functor_()); }
+  std::unique_ptr<ReturnT> result() { return std::move(result_); }
+
+ private:
+  FunctorT functor_;
+  std::unique_ptr<ReturnT> result_;
+};
+
 // Specialization for ReturnT of void.
 template <class FunctorT>
 class FunctorMessageHandler<void, FunctorT> : public MessageHandler {