Instead of marking all default apps as bookmark apps, allow it to be specified per-app.

chrome/browser/extensions/external_extension_provider_impl.h

 // Copyright (c) 2012 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_EXTERNAL_EXTENSION_PROVIDER_IMPL_H_
 #define CHROME_BROWSER_EXTENSIONS_EXTERNAL_EXTENSION_PROVIDER_IMPL_H_
 #pragma once
 
 #include <string>
 
@@ skipping 45 matching lines @@
 
   // ExternalExtensionProvider implementation:
   virtual void ServiceShutdown() OVERRIDE;
   virtual void VisitRegisteredExtension() OVERRIDE;
   virtual bool HasExtension(const std::string& id) const OVERRIDE;
   virtual bool GetExtensionDetails(const std::string& id,
                                    Extension::Location* location,
                                    scoped_ptr<Version>* version) const OVERRIDE;
 
   virtual bool IsReady() const OVERRIDE;
-  virtual int GetCreationFlags() const OVERRIDE;
 
   static const char kExternalCrx[];
   static const char kExternalVersion[];
   static const char kExternalUpdateUrl[];
   static const char kSupportedLocales[];
+  static const char kIsBookmarkApp[];
 
   void set_auto_acknowledge(bool auto_acknowledge) {
     auto_acknowledge_ = auto_acknowledge;
   }
 
  private:
   // Location for external extensions that are provided by this provider from
   // local crx files.
   const Extension::Location crx_location_;
 
@@ skipping 21 matching lines @@
   int creation_flags_;
 
   // Whether loaded extensions should be automatically acknowledged, so that
   // the user doesn't see an alert about them.
   bool auto_acknowledge_;
 
   DISALLOW_COPY_AND_ASSIGN(ExternalExtensionProviderImpl);
 };
 
 #endif  // CHROME_BROWSER_EXTENSIONS_EXTERNAL_EXTENSION_PROVIDER_IMPL_H_