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

ui/message_center/message_center_tray_unittest.cc

Index: ui/message_center/message_center_tray_unittest.cc
diff --git a/ui/message_center/message_center_tray_unittest.cc b/ui/message_center/message_center_tray_unittest.cc
index 6a68b2b989f4037d2b3f222ebe00a17320fb75bd..f9f10e1807eec6ccdfd9b71a5cd3dc01929e4a20 100644
--- a/ui/message_center/message_center_tray_unittest.cc
+++ b/ui/message_center/message_center_tray_unittest.cc
@@ -42,6 +42,8 @@ class MockDelegate : public MessageCenterTrayDelegate {
   DISALLOW_COPY_AND_ASSIGN(MockDelegate);
 };
 
+}  // namespace
+
 class MessageCenterTrayTest : public testing::Test {
  public:
   MessageCenterTrayTest() {}
@@ -63,6 +65,10 @@ class MessageCenterTrayTest : public testing::Test {
   }
 
  protected:
+  NotifierId DummyNotifierId() {
+    return NotifierId();
+  }
+
   void AddNotification(const std::string& id) {
     scoped_ptr<Notification> notification(
         new Notification(message_center::NOTIFICATION_TYPE_SIMPLE,
@@ -71,7 +77,7 @@ class MessageCenterTrayTest : public testing::Test {
                          ASCIIToUTF16("Notification message body."),
                          gfx::Image(),
                          ASCIIToUTF16("www.test.org"),
-                         NotifierId(),
+                         DummyNotifierId(),
                          message_center::RichNotificationData(),
                          NULL /* delegate */));
     message_center_->AddNotification(notification.Pass());
@@ -84,8 +90,6 @@ class MessageCenterTrayTest : public testing::Test {
   DISALLOW_COPY_AND_ASSIGN(MessageCenterTrayTest);
 };
 
-}  // namespace
-
 TEST_F(MessageCenterTrayTest, BasicMessageCenter) {
   ASSERT_FALSE(message_center_tray_->popups_visible());
   ASSERT_FALSE(message_center_tray_->message_center_visible());
@@ -178,7 +182,7 @@ TEST_F(MessageCenterTrayTest, MessageCenterReopenPopupsForSystemPriority) {
                        ASCIIToUTF16("Notification message body."),
                        gfx::Image(),
                        ASCIIToUTF16("www.test.org"),
-                       NotifierId(),
+                       DummyNotifierId(),
                        message_center::RichNotificationData(),
                        NULL /* delegate */));
   notification->SetSystemPriority();