Cleanup: Remove unneeded forward declarations in webkit/plugins/.

webkit/plugins/ppapi/ppb_graphics_2d_impl.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 WEBKIT_PLUGINS_PPAPI_PPB_GRAPHICS_2D_IMPL_H_
 #define WEBKIT_PLUGINS_PPAPI_PPB_GRAPHICS_2D_IMPL_H_
 
 #include <vector>
 
 #include "base/basictypes.h"
 #include "base/memory/weak_ptr.h"
 #include "ppapi/c/pp_completion_callback.h"
 #include "ppapi/c/ppb_graphics_2d.h"
 #include "ppapi/shared_impl/resource.h"
 #include "ppapi/thunk/ppb_graphics_2d_api.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebCanvas.h"
 
 struct PPB_Graphics2D;
 
 namespace gfx {
 class Rect;
 }
 
 namespace webkit {
 namespace ppapi {
 
 class PPB_ImageData_Impl;
 class PluginInstance;
-class PluginModule;
 
 class PPB_Graphics2D_Impl : public ::ppapi::Resource,
                             public ::ppapi::thunk::PPB_Graphics2D_API {
  public:
   virtual ~PPB_Graphics2D_Impl();
 
   static PP_Resource Create(PP_Instance instance,
                             const PP_Size& size,
                             PP_Bool is_always_opaque);
 
@@ skipping 39 matching lines @@
 
   bool Init(int width, int height, bool is_always_opaque);
 
   // Tracks a call to flush that requires a callback.
   class FlushCallbackData {
    public:
     FlushCallbackData() {
       Clear();
     }
 
-    FlushCallbackData(const PP_CompletionCallback& callback) {
+    explicit FlushCallbackData(const PP_CompletionCallback& callback) {
       Set(callback);
     }
 
     bool is_null() const { return !callback_.func; }
 
     void Set(const PP_CompletionCallback& callback) {
       callback_ = callback;
     }
 
     void Clear() {
@@ skipping 77 matching lines @@
 
   base::WeakPtrFactory<PPB_Graphics2D_Impl> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(PPB_Graphics2D_Impl);
 };
 
 }  // namespace ppapi
 }  // namespace webkit
 
 #endif  // WEBKIT_PLUGINS_PPAPI_PPB_GRAPHICS_2D_IMPL_H_