Cleanup: Remove unneeded forward declarations in webkit/.

webkit/glue/scoped_clipboard_writer_glue.h

-// Copyright (c) 2009 The Chromium Authors. All rights reserved.
+// 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 SCOPED_CLIPBOARD_WRITER_GLUE_H_
-#define SCOPED_CLIPBOARD_WRITER_GLUE_H_
+#ifndef WEBKIT_GLUE_SCOPED_CLIPBOARD_WRITER_GLUE_H_
+#define WEBKIT_GLUE_SCOPED_CLIPBOARD_WRITER_GLUE_H_
 
 #include "ui/base/clipboard/scoped_clipboard_writer.h"
 
-class SkBitmap;
-
 namespace base {
 class SharedMemory;
 }
 
 class ScopedClipboardWriterGlue : public ui::ScopedClipboardWriter {
  public:
-   ScopedClipboardWriterGlue(ui::Clipboard* clipboard)
+  explicit ScopedClipboardWriterGlue(ui::Clipboard* clipboard)
       : ui::ScopedClipboardWriter(clipboard),
         shared_buf_(NULL) {
   }
 
   ~ScopedClipboardWriterGlue();
 
   void WriteBitmapFromPixels(const void* pixels, const gfx::Size& size);
 
  private:
   base::SharedMemory* shared_buf_;
   DISALLOW_COPY_AND_ASSIGN(ScopedClipboardWriterGlue);
 };
 
-#endif  // SCOPED_CLIPBOARD_WRITER_GLUE_H_
+#endif  // WEBKIT_GLUE_SCOPED_CLIPBOARD_WRITER_GLUE_H_