Rewrite clipboard write IPC handling to be easier to understand.

content/renderer/renderer_clipboard_delegate.h

Index: content/renderer/renderer_clipboard_delegate.h
diff --git a/content/renderer/renderer_clipboard_delegate.h b/content/renderer/renderer_clipboard_delegate.h
new file mode 100644
index 0000000000000000000000000000000000000000..ef8e034fce9ba8f8513c470d72f68df13a0f23b2
--- /dev/null
+++ b/content/renderer/renderer_clipboard_delegate.h
@@ -0,0 +1,66 @@
+// Copyright (c) 2012 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_RENDERER_CLIPBOARD_DELEGATE_H_
+#define CONTENT_RENDERER_RENDERER_CLIPBOARD_DELEGATE_H_
+
+#include <stdint.h>
+#include <map>
+#include <string>
+#include <vector>
+
+#include "base/compiler_specific.h"
+#include "base/macros.h"
+#include "base/strings/string16.h"
+#include "content/common/clipboard_format.h"
+#include "ui/base/clipboard/clipboard_types.h"
+
+class GURL;
+class SkBitmap;
+
+namespace content {
+
+// Renderer interface to read/write from the clipboard over IPC.
+class RendererClipboardDelegate {
+ public:
+  RendererClipboardDelegate();
+
+  uint64 GetSequenceNumber(ui::ClipboardType type);
+  bool IsFormatAvailable(ClipboardFormat format, ui::ClipboardType type);
+  void Clear(ui::ClipboardType type);
+  void ReadAvailableTypes(ui::ClipboardType type,
+                          std::vector<base::string16>* types,
+                          bool* contains_filenames);
+  void ReadText(ui::ClipboardType type, base::string16* result);
+  void ReadHTML(ui::ClipboardType type,
+                base::string16* markup,
+                GURL* url,
+                uint32* fragment_start,
+                uint32* fragment_end);
+  void ReadRTF(ui::ClipboardType type, std::string* result);
+  void ReadImage(ui::ClipboardType type, std::string* data);
+  void ReadCustomData(ui::ClipboardType clipboard_type,
+                      const base::string16& type,
+                      base::string16* data);
+
+  void WriteText(ui::ClipboardType type, const base::string16& text);
+  void WriteHTML(ui::ClipboardType type,
+                 const base::string16& markup,
+                 const GURL& url);
+  void WriteSmartPasteMarker(ui::ClipboardType type);
+  void WriteCustomData(ui::ClipboardType type,
+                       const std::map<base::string16, base::string16>& data);
+  void WriteBookmark(ui::ClipboardType type,
+                     const GURL& url,
+                     const base::string16& title);
+  bool WriteImage(ui::ClipboardType type, const SkBitmap& bitmap);
+  void CommitWrite(ui::ClipboardType type);
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(RendererClipboardDelegate);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_RENDERER_RENDERER_CLIPBOARD_DELEGATE_H_