Use initializer_list in ChromePermissionMessageRule ctors

chrome/common/extensions/permissions/chrome_permission_message_rules.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/common/extensions/permissions/chrome_permission_message_rules.h"
 
 #include "base/macros.h"
 #include "base/stl_util.h"
 #include "base/strings/string_util.h"
 #include "base/strings/utf_string_conversions.h"
@@ skipping 237 matching lines @@
     return PermissionMessage(
         l10n_util::GetStringUTF16(IDS_EXTENSION_PROMPT_WARNING_USB_DEVICE_LIST),
         permissions, submessages);
   }
 
   DISALLOW_COPY_AND_ASSIGN(USBDevicesFormatter);
 };
 
 }  // namespace
 
-// Convenience constructors to allow inline initialization of the permission
-// ID sets.
-// TODO(treib): Once we're allowed to use uniform initialization (and
-// std::initializer_list), get rid of this helper.
-class ChromePermissionMessageRule::PermissionIDSetInitializer
-    : public std::set<APIPermission::ID> {
- public:
-  template <typename... IDs>
-  PermissionIDSetInitializer(IDs... ids) {
-    // This effectively calls insert() with each of the ids.
-    ExpandHelper(insert(ids)...);
-  }
-
-  virtual ~PermissionIDSetInitializer() {}
-
- private:
-  template <typename... Args>
-  void ExpandHelper(Args&&...) {}
-};
-
 ChromePermissionMessageRule::ChromePermissionMessageRule(
     int message_id,
-    const PermissionIDSetInitializer& required,
-    const PermissionIDSetInitializer& optional)
+    const std::initializer_list<APIPermission::ID>& required,
+    const std::initializer_list<APIPermission::ID>& optional)
     : ChromePermissionMessageRule(
           new DefaultPermissionMessageFormatter(message_id),
           required,
           optional) {}
 
 ChromePermissionMessageRule::ChromePermissionMessageRule(
     ChromePermissionMessageFormatter* formatter,
-    const PermissionIDSetInitializer& required,
-    const PermissionIDSetInitializer& optional)
+    const std::initializer_list<APIPermission::ID>& required,
+    const std::initializer_list<APIPermission::ID>& optional)
     : required_permissions_(required),
       optional_permissions_(optional),
       formatter_(formatter) {
   DCHECK(!required_permissions_.empty());
 }
 
 ChromePermissionMessageRule::ChromePermissionMessageRule(
     const ChromePermissionMessageRule& other) = default;
 
 ChromePermissionMessageRule::~ChromePermissionMessageRule() {
@@ skipping 343 matching lines @@
       {IDS_EXTENSION_PROMPT_WARNING_DISPLAY_SOURCE,
        {APIPermission::kDisplaySource},
        {}},
   };
 
   return std::vector<ChromePermissionMessageRule>(
       rules_arr, rules_arr + arraysize(rules_arr));
 }
 
 }  // namespace extensions