Disallow WebSQL and localStorage in platform apps.

chrome/browser/extensions/extension_webkit_preferences.cc

 // 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.
 
 #include "chrome/browser/extensions/extension_webkit_preferences.h"
 
 #include "chrome/common/extensions/extension.h"
 #include "webkit/glue/webpreferences.h"
 
 namespace extension_webkit_preferences {
 
 void SetPreferences(const Extension* extension,
                     content::ViewType render_view_type,
                     WebPreferences* webkit_prefs) {
-  if (extension && !extension->is_hosted_app()) {
+  if (!extension)
+    return;
+
+  if (!extension->is_hosted_app()) {
     // Extensions are trusted so we override any user preferences for disabling
     // javascript or images.
     webkit_prefs->loads_images_automatically = true;
     webkit_prefs->javascript_enabled = true;
 
     // Tabs aren't typically allowed to close windows. But extensions shouldn't
     // be subject to that.
     webkit_prefs->allow_scripts_to_close_windows = true;
 
     // Disable anything that requires the GPU process for background pages.
     // See http://crbug.com/64512 and http://crbug.com/64841.
     if (render_view_type == chrome::VIEW_TYPE_EXTENSION_BACKGROUND_PAGE) {
       webkit_prefs->experimental_webgl_enabled = false;
       webkit_prefs->accelerated_compositing_enabled = false;
       webkit_prefs->accelerated_2d_canvas_enabled = false;
     }
   }
-  if (extension) {
-    // Enable WebGL features that regular pages can't access, since they add
-    // more risk of fingerprinting.
-    webkit_prefs->privileged_webgl_extensions_enabled = true;
+
+  if (extension->is_platform_app()) {
+    webkit_prefs->databases_enabled = false;
+    webkit_prefs->local_storage_enabled = false;
   }
+
+  // Enable WebGL features that regular pages can't access, since they add
+  // more risk of fingerprinting.
+  webkit_prefs->privileged_webgl_extensions_enabled = true;
 }
 
 }  // extension_webkit_preferences