Refactor bookmark clipboard code to be cross platform.

chrome/browser/bookmarks/bookmark_drag_data.h

Index: chrome/browser/bookmarks/bookmark_drag_data.h
===================================================================
--- chrome/browser/bookmarks/bookmark_drag_data.h	(revision 22359)
+++ chrome/browser/bookmarks/bookmark_drag_data.h	(working copy)
@@ -71,6 +71,17 @@
   explicit BookmarkDragData(const BookmarkNode* node);
   explicit BookmarkDragData(const std::vector<const BookmarkNode*>& nodes);
 
+  // TODO(estade): Port to mac. It should be as simple as removing this ifdef
+  // after the relevant Clipboard functions are implemetned.
+#if !defined(OS_MACOSX)
+  // Writes elements to the clipboard.
+  void WriteToClipboard(Profile* profile) const;
+
+  // Reads bookmarks from the clipboard. Prefers data written via
+  // WriteToClipboard but will also attempt to read a plain bookmark.
+  bool ReadFromClipboard();
+#endif
+
 #if defined(TOOLKIT_VIEWS)
   // Writes elements to data. If there is only one element and it is a URL
   // the URL and title are written to the clipboard in a format other apps can
@@ -114,6 +125,9 @@
   // The actual elements written to the clipboard.
   std::vector<Element> elements;
 
+  // The MIME type for the clipboard format for BookmarkDragData.
+  static const char* kClipboardFormatString;
+
  private:
   // Path of the profile we originated from.
 #if defined(WCHAR_T_IS_UTF16)