Ok, here is a different approach at this change.

chrome/browser/extensions/extensions_service.h

 // Copyright (c) 2009 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_EXTENSIONS_EXTENSIONS_SERVICE_H_
 #define CHROME_BROWSER_EXTENSIONS_EXTENSIONS_SERVICE_H_
 
 #include <map>
 #include <set>
 #include <string>
@@ skipping 234 matching lines @@
   void LoadInstalledExtension(
       DictionaryValue* manifest, const std::string& id,
       const FilePath& path, Extension::Location location);
 
   // Handles sending notification that |extension| was loaded.
   void NotifyExtensionLoaded(Extension* extension);
 
   // Handles sending notification that |extension| was unloaded.
   void NotifyExtensionUnloaded(Extension* extension);
 
+  // Helper that updates the active extension list used for crash reporting.
+  void UpdateActiveExtensionsInCrashReporter();
+
   // The profile this ExtensionsService is part of.
   Profile* profile_;
 
   // Preferences for the owning profile.
   scoped_ptr<ExtensionPrefs> extension_prefs_;
 
   // The current list of installed extensions.
   ExtensionList extensions_;
 
   // The list of installed extensions that have been disabled.
@@ skipping 119 matching lines @@
 
   // A map of all external extension providers.
   typedef std::map<Extension::Location,
                    linked_ptr<ExternalExtensionProvider> > ProviderMap;
   ProviderMap external_extension_providers_;
 
   DISALLOW_COPY_AND_ASSIGN(ExtensionsServiceBackend);
 };
 
 #endif  // CHROME_BROWSER_EXTENSIONS_EXTENSIONS_SERVICE_H_