Rewrite clipboard write IPC handling to be easier to understand.

content/renderer/webclipboard_impl.h

 // Copyright (c) 2013 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 CONTENT_RENDERER_WEBCLIPBOARD_IMPL_H_
 #define CONTENT_RENDERER_WEBCLIPBOARD_IMPL_H_
 
 #include "base/compiler_specific.h"
-
 #include "third_party/WebKit/public/platform/WebClipboard.h"
 #include "ui/base/clipboard/clipboard.h"
 
 #include <string>
 
 namespace content {
-class ClipboardClient;
+class RendererClipboardDelegate;
 
 class WebClipboardImpl : public blink::WebClipboard {
  public:
-  explicit WebClipboardImpl(ClipboardClient* client);
+  explicit WebClipboardImpl(RendererClipboardDelegate* delegate);
 
   virtual ~WebClipboardImpl();
 
   // WebClipboard methods:
   virtual uint64 sequenceNumber(Buffer buffer);
   virtual bool isFormatAvailable(Format format, Buffer buffer);
   virtual blink::WebVector<blink::WebString> readAvailableTypes(
       Buffer buffer, bool* contains_filenames);
   virtual blink::WebString readPlainText(Buffer buffer);
   virtual blink::WebString readHTML(
@@ skipping 11 matching lines @@
       const blink::WebString& plain_text,
       bool write_smart_paste);
   virtual void writeImage(
       const blink::WebImage& image,
       const blink::WebURL& source_url,
       const blink::WebString& title);
   virtual void writeDataObject(const blink::WebDragData& data);
 
  private:
   bool ConvertBufferType(Buffer, ui::ClipboardType*);
-  ClipboardClient* client_;
+  RendererClipboardDelegate* const delegate_;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_WEBCLIPBOARD_IMPL_H_