Commiting the changes from my previous cl that are specific to not including ...

chrome/common/render_messages_internal.h

 // Copyright (c) 2006-2008 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.
 
 // This header is meant to be included in multiple passes, hence no traditional
 // header guard.
 // See ipc_message_macros.h for explanation of the macros and passes.
 
 #include <string>
 #include <vector>
@@ skipping 718 matching lines @@
                              std::wstring /* in - default prompt */,
                              int          /* in - dialog flags */,
                              bool         /* out - success */,
                              std::wstring /* out - prompt field */)
 
   // Sets the contents for the given page (URL and page ID are the first two
   // arguments) given the contents that is the 3rd.
   IPC_MESSAGE_CONTROL3(ViewHostMsg_PageContents, GURL, int32, std::wstring)
 
   // Specifies the URL as the first parameter (a wstring) and thumbnail as
-  // binary data as the second parameter. Our macros don't handle binary data,
-  // so this is declared "empty," to be encoded by the caller/receiver.
-  IPC_MESSAGE_EMPTY(ViewHostMsg_Thumbnail)
+  // binary data as the second parameter.
+  IPC_MESSAGE_ROUTED3(ViewHostMsg_Thumbnail,
+                      GURL /* url */,
+                      ThumbnailScore /* score */,
+                      SkBitmap /* bitmap */)
 
   // Notification that the url for the favicon of a site has been determined.
   IPC_MESSAGE_ROUTED2(ViewHostMsg_UpdateFavIconURL,
                       int32 /* page_id */,
                       GURL /* url of the favicon */)
 
   // Used to tell the parent that the user right clicked on an area of the
   // content area, and a context menu should be shown for it. The params
   // object contains information about the node(s) that were selected when the
   // user right clicked.
@@ skipping 348 matching lines @@
 
   // Get the list of proxies to use for |url|, as a semicolon delimited list
   // of "<TYPE> <HOST>:<PORT>" | "DIRECT". See also
   // PluginProcessHostMsg_ResolveProxy which does the same thing.
   IPC_SYNC_MESSAGE_CONTROL1_2(ViewHostMsg_ResolveProxy,
                               GURL /* url */,
                               int /* network error */,
                               std::string /* proxy list */)
 
 IPC_END_MESSAGES(ViewHost)