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diff --git a/webrtc/base/messagehandler.h b/webrtc/base/messagehandler.h
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+/*
+ *  Copyright 2004 The WebRTC Project Authors. All rights reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#ifndef WEBRTC_BASE_MESSAGEHANDLER_H_
+#define WEBRTC_BASE_MESSAGEHANDLER_H_
+
+#include "webrtc/base/constructormagic.h"
+#include "webrtc/base/scoped_ptr.h"
+
+namespace rtc {
+
+struct Message;
+
+// Messages get dispatched to a MessageHandler
+
+class MessageHandler {
+ public:
+  virtual ~MessageHandler();
+  virtual void OnMessage(Message* msg) = 0;
+
+ protected:
+  MessageHandler() {}
+
+ private:
+  RTC_DISALLOW_COPY_AND_ASSIGN(MessageHandler);
+};
+
+// Helper class to facilitate executing a functor on a thread.
+template <class ReturnT, class FunctorT>
+class FunctorMessageHandler : public MessageHandler {
+ public:
+  explicit FunctorMessageHandler(const FunctorT& functor)
+      : functor_(functor) {}
+  virtual void OnMessage(Message* msg) {
+    result_ = functor_();
+  }
+  const ReturnT& result() const { return result_; }
+
+ private:
+  FunctorT functor_;
+  ReturnT result_;
+};
+
+// Specialization for rtc::scoped_ptr<ReturnT>.
+template <class ReturnT, class FunctorT>
+class FunctorMessageHandler<class rtc::scoped_ptr<ReturnT>, FunctorT>
+    : public MessageHandler {
+ public:
+  explicit FunctorMessageHandler(const FunctorT& functor) : functor_(functor) {}
+  virtual void OnMessage(Message* msg) { result_ = functor_().Pass(); }
+  rtc::scoped_ptr<ReturnT> result() { return result_.Pass(); }
+
+ private:
+  FunctorT functor_;
+  rtc::scoped_ptr<ReturnT> result_;
+};
+
+// Specialization for ReturnT of void.
+template <class FunctorT>
+class FunctorMessageHandler<void, FunctorT> : public MessageHandler {
+ public:
+  explicit FunctorMessageHandler(const FunctorT& functor)
+      : functor_(functor) {}
+  virtual void OnMessage(Message* msg) {
+    functor_();
+  }
+  void result() const {}
+
+ private:
+  FunctorT functor_;
+};
+
+} // namespace rtc
+
+#endif // WEBRTC_BASE_MESSAGEHANDLER_H_