Move talk/app/webrtc to webrtc/api

webrtc/api/notifier.h

Index: webrtc/api/notifier.h
diff --git a/webrtc/api/notifier.h b/webrtc/api/notifier.h
new file mode 100644
index 0000000000000000000000000000000000000000..8be9ffe9dc0166c93e0707fc04a5ad3b4534934d
--- /dev/null
+++ b/webrtc/api/notifier.h
@@ -0,0 +1,60 @@
+/*
+ *  Copyright 2011 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_API_NOTIFIER_H_
+#define WEBRTC_API_NOTIFIER_H_
+
+#include <list>
+
+#include "webrtc/api/mediastreaminterface.h"
+#include "webrtc/base/common.h"
+
+namespace webrtc {
+
+// Implement a template version of a notifier.
+template <class T>
+class Notifier : public T {
+ public:
+  Notifier() {
+  }
+
+  virtual void RegisterObserver(ObserverInterface* observer) {
+    ASSERT(observer != NULL);
+    observers_.push_back(observer);
+  }
+
+  virtual void UnregisterObserver(ObserverInterface* observer) {
+    for (std::list<ObserverInterface*>::iterator it = observers_.begin();
+         it != observers_.end(); it++) {
+      if (*it == observer) {
+        observers_.erase(it);
+        break;
+      }
+    }
+  }
+
+  void FireOnChanged() {
+    // Copy the list of observers to avoid a crash if the observer object
+    // unregisters as a result of the OnChanged() call. If the same list is used
+    // UnregisterObserver will affect the list make the iterator invalid.
+    std::list<ObserverInterface*> observers = observers_;
+    for (std::list<ObserverInterface*>::iterator it = observers.begin();
+         it != observers.end(); ++it) {
+      (*it)->OnChanged();
+    }
+  }
+
+ protected:
+  std::list<ObserverInterface*> observers_;
+};
+
+}  // namespace webrtc
+
+#endif  // WEBRTC_API_NOTIFIER_H_