Do not show the install prompt for themes.

chrome/browser/extensions/bundle_installer.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_BUNDLE_INSTALLER_H_
 #define CHROME_BROWSER_EXTENSIONS_BUNDLE_INSTALLER_H_
 #pragma once
 
 #include <string>
 #include <vector>
 
 #include "base/memory/linked_ptr.h"
+#include "base/memory/scoped_ptr.h"
 #include "base/string16.h"
 #include "chrome/browser/extensions/extension_install_ui.h"
 #include "chrome/browser/extensions/webstore_installer.h"
 #include "chrome/browser/extensions/webstore_install_helper.h"
 #include "chrome/browser/ui/browser_list.h"
 #include "chrome/common/extensions/extension.h"
 
 namespace base {
 class DictionaryValue;
 }  // namespace base
@@ skipping 154 matching lines @@
 
   // Holds the bundle's Items, indexed by their ids.
   ItemMap items_;
 
   // The browser to show the confirmation bubble for.
   Browser* browser_;
 
   // The profile that the bundle should be installed in.
   Profile* profile_;
 
+  // The UI that shows the confirmation prompt.
+  scoped_ptr<ExtensionInstallUI> install_ui_;
+
   Delegate* delegate_;
 
   DISALLOW_COPY_AND_ASSIGN(BundleInstaller);
 };
 
 }  // namespace extensions
 
 #endif  // CHROME_BROWSER_EXTENSIONS_BUNDLE_INSTALLER_H_