Attempt 2 at this. This differs from first version in that I renamed...

chrome/browser/bookmarks/bookmark_model.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.
 
 #ifndef CHROME_BROWSER_BOOKMARKS_BOOKMARK_BAR_MODEL_H_
 #define CHROME_BROWSER_BOOKMARKS_BOOKMARK_BAR_MODEL_H_
 
 #include "build/build_config.h"
 
 #include "base/lock.h"
@@ skipping 266 matching lines @@
                      const std::wstring& title,
                      bool is_starred);
 
   // Resets the 'date modified' time of the node to 0. This is used during
   // importing to exclude the newly created groups from showing up in the
   // combobox of most recently modified groups.
   void ResetDateGroupModified(BookmarkNode* node);
 
   Profile* profile() const { return profile_; }
 
+  // Sets the store to NULL, making it so the BookmarkModel does not persist
+  // any changes to disk. This is only useful during testing to speed up
+  // testing.
+  void ClearStore();
+
  private:
   // Used to order BookmarkNodes by URL.
   class NodeURLComparator {
    public:
     bool operator()(BookmarkNode* n1, BookmarkNode* n2) const {
       return n1->GetURL() < n2->GetURL();
     }
   };
 
   // Implementation of IsBookmarked. Before calling this the caller must
@@ skipping 123 matching lines @@
   // TODO(port): Implement for other platforms.
 
   // Handle to event signaled when loading is done.
   ScopedHandle loaded_signal_;
 #endif
 
   DISALLOW_COPY_AND_ASSIGN(BookmarkModel);
 };
 
 #endif  // CHROME_BROWSER_BOOKMARKS_BOOKMARK_BAR_MODEL_H_