Replace more ObserverList with base::ObserverList.

ppapi/proxy/host_dispatcher.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef PPAPI_PROXY_HOST_DISPATCHER_H_
 #define PPAPI_PROXY_HOST_DISPATCHER_H_
 
 #include <map>
 #include <string>
 #include <vector>
@@ skipping 124 matching lines @@
   // Guaranteed non-NULL.
   const PPB_Proxy_Private* ppb_proxy_;
 
   // Set to true when the plugin is in a state that it can be reentered by a
   // sync message from the host. We allow reentrancy only when we're processing
   // a sync message from the renderer that is a scripting command. When the
   // plugin is in this state, it needs to accept reentrancy since scripting may
   // ultimately call back into the plugin.
   bool allow_plugin_reentrancy_;
 
-  ObserverList<SyncMessageStatusObserver> sync_status_observer_list_;
+  base::ObserverList<SyncMessageStatusObserver> sync_status_observer_list_;
 
   std::vector<IPC::Listener*> filters_;
 
   base::WeakPtrFactory<HostDispatcher> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(HostDispatcher);
 };
 
 // Create this object on the stack to prevent the module (and hence the
 // dispatcher) from being deleted out from under you. This is necessary when
 // calling some scripting functions that may delete the plugin.
 //
 // This class does nothing if used on the plugin side.
 class ScopedModuleReference {
  public:
   explicit ScopedModuleReference(Dispatcher* dispatcher);
   ~ScopedModuleReference();
 
  private:
   HostDispatcher* dispatcher_;
 
   DISALLOW_COPY_AND_ASSIGN(ScopedModuleReference);
 };
 
 }  // namespace proxy
 }  // namespace ppapi
 
 #endif  // PPAPI_PROXY_HOST_DISPATCHER_H_