Extend contextMenus API to support browser/page actions

chrome/browser/extensions/api/context_menus/context_menus_api_helpers.cc

 // Copyright 2014 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/api/context_menus/context_menus_api_helpers.h"
 
 #include "base/strings/string_number_conversions.h"
 
 namespace extensions {
 namespace context_menus_api_helpers {
 
+const char kActionNotAllowedError[] =
+    "Only extensions are allowed to use action contexts";
 const char kCannotFindItemError[] = "Cannot find menu item with id *";
 const char kCheckedError[] =
     "Only items with type \"radio\" or \"checkbox\" can be checked";
 const char kDuplicateIDError[] =
     "Cannot create item with duplicate id *";
 const char kGeneratedIdKey[] = "generatedId";
 const char kLauncherNotAllowedError[] =
     "Only packaged apps are allowed to use 'launcher' context";
 const char kOnclickDisallowedError[] = "Extensions using event pages cannot "
     "pass an onclick parameter to chrome.contextMenus.create. Instead, use "
@@ skipping 22 matching lines @@
   }
   if (parent->type() != MenuItem::NORMAL) {
     *error = kParentsMustBeNormalError;
     return NULL;
   }
   return parent;
 }
 
 }  // namespace context_menus_api_helpers
 }  // namespace extensions