Cleanup: Remove unneeded forward declarations in ppapi.

ppapi/proxy/ppb_context_3d_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_PROXY_PPB_CONTEXT_3D_PROXY_H_
 #define PPAPI_PROXY_PPB_CONTEXT_3D_PROXY_H_
 
 #include <vector>
 
 #include "base/memory/scoped_ptr.h"
 #include "base/shared_memory.h"
 #include "gpu/command_buffer/common/command_buffer.h"
 #include "ppapi/c/pp_graphics_3d.h"
 #include "ppapi/c/pp_instance.h"
 #include "ppapi/proxy/interface_proxy.h"
 #include "ppapi/proxy/proxy_non_thread_safe_ref_count.h"
 #include "ppapi/shared_impl/resource.h"
 #include "ppapi/thunk/ppb_context_3d_api.h"
 
-struct PPB_Context3D_Dev;
-struct PPB_Context3DTrusted_Dev;
-
 namespace gpu {
 class CommandBuffer;
 
 namespace gles2 {
 class GLES2CmdHelper;
 class GLES2Implementation;
 }  // namespace gles2
 
 }  // namespace gpu
 
@@ skipping 54 matching lines @@
   scoped_ptr<gpu::CommandBuffer> command_buffer_;
   scoped_ptr<gpu::gles2::GLES2CmdHelper> helper_;
   int32 transfer_buffer_id_;
   scoped_ptr<gpu::gles2::GLES2Implementation> gles2_impl_;
 
   DISALLOW_COPY_AND_ASSIGN(Context3D);
 };
 
 class PPB_Context3D_Proxy : public InterfaceProxy {
  public:
-  PPB_Context3D_Proxy(Dispatcher* dispatcher);
+  explicit PPB_Context3D_Proxy(Dispatcher* dispatcher);
   virtual ~PPB_Context3D_Proxy();
 
   static PP_Resource Create(PP_Instance instance,
                             PP_Config3D_Dev config,
                             PP_Resource share_context,
                             const int32_t* attrib_list);
 
   // InterfaceProxy implementation.
   virtual bool OnMessageReceived(const IPC::Message& msg);
 
@@ skipping 27 matching lines @@
   void OnMsgGetTransferBuffer(const HostResource& context,
                               int32 id,
                               base::SharedMemoryHandle* transfer_buffer,
                               uint32* size);
 };
 
 }  // namespace proxy
 }  // namespace ppapi
 
 #endif  // PPAPI_PROXY_PPB_CONTEXT_3D_PROXY_H_