Remove bookmark_model.h includes from places where it is not needed.

chrome/browser/bookmarks/bookmark_codec.h

 // 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 CHROME_BROWSER_BOOKMARKS_BOOKMARK_CODEC_H_
 #define CHROME_BROWSER_BOOKMARKS_BOOKMARK_CODEC_H_
 
 #include <set>
 #include <string>
 
 #include "base/basictypes.h"
 #include "base/md5.h"
 #include "base/strings/string16.h"
-#include "chrome/browser/bookmarks/bookmark_model.h"
+#include "components/bookmarks/core/browser/bookmark_node.h"
 
 class BookmarkModel;
-class BookmarkNode;
 
 namespace base {
 class DictionaryValue;
 class ListValue;
 class Value;
 }
 
 // BookmarkCodec is responsible for encoding and decoding the BookmarkModel
 // into JSON values. The encoded values are written to disk via the
 // BookmarkStorage.
@@ skipping 171 matching lines @@
   // Meta info set on bookmark model root.
   BookmarkNode::MetaInfoMap model_meta_info_map_;
 
   // Sync transaction version set on bookmark model root.
   int64 model_sync_transaction_version_;
 
   DISALLOW_COPY_AND_ASSIGN(BookmarkCodec);
 };
 
 #endif  // CHROME_BROWSER_BOOKMARKS_BOOKMARK_CODEC_H_