[Signin Error Dialog] (3/3) Added the triggering code

chrome/browser/ui/webui/signin/login_ui_service.h

Index: chrome/browser/ui/webui/signin/login_ui_service.h
diff --git a/chrome/browser/ui/webui/signin/login_ui_service.h b/chrome/browser/ui/webui/signin/login_ui_service.h
index 6f6ecad91e4e70773e35741c59184f06fcdd0948..ff46d43afd6ce865776eaaa481df824be776916f 100644
--- a/chrome/browser/ui/webui/signin/login_ui_service.h
+++ b/chrome/browser/ui/webui/signin/login_ui_service.h
@@ -79,8 +79,12 @@ class LoginUIService : public KeyedService {
   // chrome://signin to ask the user to sign in to chrome.
   void ShowLoginPopup();
 
-  // Displays login results.
-  void DisplayLoginResult(Browser* browser, const base::string16& message);
+  // Displays login results. This is either the Modal Signin Error dialog if
+  // |error_message| is a non-empty string, or the User Menu with a blue header
+  // toast otherwise.
+  void DisplayLoginResult(Browser* browser,
+                          const base::string16& error_message,
+                          const base::string16& email);
 
   // Gets the last login result set through |DisplayLoginResult|.
   const base::string16& GetLastLoginResult() const;