Do not allow creating dummy notifier id from production, for safety.

ui/message_center/notifier_settings.h

 // Copyright (c) 2013 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 UI_MESSAGE_CENTER_NOTIFIER_SETTINGS_H_
 #define UI_MESSAGE_CENTER_NOTIFIER_SETTINGS_H_
 
 #include <string>
 
+#include "base/gtest_prod_util.h"
 #include "base/strings/string16.h"
 #include "ui/gfx/image/image.h"
 #include "ui/message_center/message_center_export.h"
 #include "url/gurl.h"
 
+FORWARD_DECLARE_TEST(MessageCenterTrayBridgeTest,
+                     StatusItemOnlyAfterFirstNotification);
+
+namespace ash {
+class WebNotificationTrayTest;
+}
+
 namespace message_center {
+namespace test {
+class MessagePopupCollectionTest;
+}
 
 class NotifierSettingsDelegate;
 class NotifierSettingsProvider;
 
 // Brings up the settings dialog and returns a weak reference to the delegate,
 // which is typically the view. If the dialog already exists, it is brought to
 // the front, otherwise it is created.
 MESSAGE_CENTER_EXPORT NotifierSettingsDelegate* ShowSettings(
     NotifierSettingsProvider* provider,
     gfx::NativeView context);
 
 // The struct to distinguish the notifiers.
 struct MESSAGE_CENTER_EXPORT NotifierId {
   enum NotifierType {
     APPLICATION,
     WEB_PAGE,
     SYSTEM_COMPONENT,
     SYNCED_NOTIFICATION_SERVICE,
   };
 
   // Constructor for non WEB_PAGE type.
   NotifierId(NotifierType type, const std::string& id);
 
   // Constructor for WEB_PAGE type.
   explicit NotifierId(const GURL& url);
 
-  // The default constructor which doesn't specify the notifier. Used for tests.
-  NotifierId();
-
   bool operator==(const NotifierId& other) const;
 
   NotifierType type;
 
   // The identifier of the app notifier. Empty if it's WEB_PAGE.
   std::string id;
 
   // The URL pattern of the notifer.
   GURL url;
 
   // The identifier of the profile where the notification is created. This is
   // used for ChromeOS multi-profile support and can be empty.
   std::string profile_id;
+
+ private:
+  friend class MessageCenterTrayTest;
+  friend class test::MessagePopupCollectionTest;
+  friend class NotificationControllerTest;
+  friend class PopupCollectionTest;
+  friend class TrayViewControllerTest;
+  friend class ash::WebNotificationTrayTest;
+  FRIEND_TEST_ALL_PREFIXES(::MessageCenterTrayBridgeTest,
+                           StatusItemOnlyAfterFirstNotification);
+  FRIEND_TEST_ALL_PREFIXES(PopupControllerTest, Creation);
+  FRIEND_TEST_ALL_PREFIXES(NotificationListTest, UnreadCountNoNegative);
+  FRIEND_TEST_ALL_PREFIXES(NotificationListTest, TestHasNotificationOfType);
+
+  // The default constructor which doesn't specify the notifier. Used for tests.
+  NotifierId();
 };
 
 // The struct to hold the information of notifiers. The information will be
 // used by NotifierSettingsView.
 struct MESSAGE_CENTER_EXPORT Notifier {
   Notifier(const NotifierId& notifier_id, const string16& name, bool enabled);
   ~Notifier();
 
   NotifierId notifier_id;
 
@@ skipping 93 matching lines @@
 
   // Called upon request for more information about a particular notifier.
   virtual void OnNotifierAdvancedSettingsRequested(
       const NotifierId& notifier_id,
       const std::string* notification_id) = 0;
 };
 
 }  // namespace message_center
 
 #endif  // UI_MESSAGE_CENTER_NOTIFIER_SETTINGS_H_