Use macros to define pepper interfaces

ppapi/proxy/ppb_pdf_proxy.h

 // Copyright (c) 2011 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_PPB_PDF_PROXY_H_
 #define PPAPI_PPB_PDF_PROXY_H_
 
 #include "ppapi/c/pp_module.h"
 #include "ppapi/proxy/interface_proxy.h"
 #include "ppapi/shared_impl/host_resource.h"
 
 struct PPB_PDF;
 
 namespace ppapi {
 namespace proxy {
 
 struct SerializedFontDescription;
 
 class PPB_PDF_Proxy : public InterfaceProxy {
  public:
-  PPB_PDF_Proxy(Dispatcher* dispatcher, const void* target_interface);
+  PPB_PDF_Proxy(Dispatcher* dispatcher);
   virtual ~PPB_PDF_Proxy();
 
   static const Info* GetInfo();
 
-  const PPB_PDF* ppb_pdf_target() const {
-    return static_cast<const PPB_PDF*>(target_interface());
-  }
-
   // InterfaceProxy implementation.
   virtual bool OnMessageReceived(const IPC::Message& msg);
 
  private:
   // Message handlers.
   void OnMsgGetFontFileWithFallback(PP_Module module,
                                     const SerializedFontDescription& desc,
                                     int32_t charset,
                                     ppapi::HostResource* result);
   void OnMsgGetFontTableForPrivateFontFile(const ppapi::HostResource& font_file,
                                            uint32_t table,
                                            std::string* result);
+
+  // When this proxy is in the host side, this value caches the interface
+  // pointer so we don't have to retrieve it from the dispatcher each time.
+  // In the plugin, this value is always NULL.
+  const PPB_PDF* ppb_pdf_impl_;
 };
 
 }  // namespace proxy
 }  // namespace ppapi
 
 #endif  // PPAPI_PPB_PDF_PROXY_H_