Fix clang build by removing redundant "const"

ppapi/proxy/dispatcher.h

 // Copyright (c) 2010 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_DISPATCHER_H_
 #define PPAPI_PROXY_DISPATCHER_H_
 
 #include <map>
 #include <string>
 #include <vector>
@@ skipping 37 matching lines @@
 //    InterfaceProxy ----------------------> InterfaceProxy
 //                                      |
 //                                      |
 //    "Target"                          |    "Source"
 //    InterfaceProxy <---------------------- InterfaceProxy
 //                                      |
 class Dispatcher : public IPC::Channel::Listener,
                    public IPC::Message::Sender {
  public:
   typedef const void* (*GetInterfaceFunc)(const char*);
-  typedef const int32_t (*InitModuleFunc)(PP_Module, GetInterfaceFunc);
-  typedef const void (*ShutdownModuleFunc)();
+  typedef int32_t (*InitModuleFunc)(PP_Module, GetInterfaceFunc);
+  typedef void (*ShutdownModuleFunc)();
 
   ~Dispatcher();
 
   bool InitWithChannel(MessageLoop* ipc_message_loop,
                        const std::string& channel_name,
                        bool is_client,
                        base::WaitableEvent* shutdown_event);
 
   // Returns true if the dispatcher is on the plugin side, or false if it's the
   // browser side.
@@ skipping 108 matching lines @@
 
   scoped_ptr<VarSerializationRules> serialization_rules_;
 
   DISALLOW_COPY_AND_ASSIGN(Dispatcher);
 };
 
 }  // namespace proxy
 }  // namespace pp
 
 #endif  // PPAPI_PROXY_DISPATCHER_H_