Delete unused themes from disk on shutdown.

chrome/common/extensions/extension.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_COMMON_EXTENSIONS_EXTENSION_H_
 #define CHROME_COMMON_EXTENSIONS_EXTENSION_H_
 
 #include <map>
 #include <set>
 #include <string>
@@ skipping 219 matching lines @@
   // so that the registry location can be overwritten during testing.
   Location ExternalExtensionInstallType(std::string registry_path);
 
   // Theme-related.
   DictionaryValue* GetThemeImages() const { return theme_images_.get(); }
   DictionaryValue* GetThemeColors() const { return theme_colors_.get(); }
   DictionaryValue* GetThemeTints() const { return theme_tints_.get(); }
   DictionaryValue* GetThemeDisplayProperties() const {
     return theme_display_properties_.get();
   }
-  bool IsTheme() { return is_theme_; }
+  bool IsTheme() const { return is_theme_; }
 
   // Returns a list of paths (relative to the extension dir) for images that
   // the browser might load (like themes and page action icons).
   std::set<FilePath> GetBrowserImages();
 
   // Returns an absolute path to the given icon inside of the extension. Returns
   // an empty FilePath if the extension does not have that icon.
   ExtensionResource GetIconPath(Icons icon);
 
   const DictionaryValue* manifest_value() const {
@@ skipping 140 matching lines @@
 
   // True if the background page is ready.
   bool background_page_ready_;
 
   FRIEND_TEST(ExtensionTest, LoadPageActionHelper);
 
   DISALLOW_COPY_AND_ASSIGN(Extension);
 };
 
 #endif  // CHROME_COMMON_EXTENSIONS_EXTENSION_H_