Add test for showing confirmation dialog for unsecure signin

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 99dc03c711d93e4b36454dbf7be7e97a7c784b70..bd2048b9d8201793669e3c487db0fb587a2303be 100644
--- a/chrome/browser/ui/webui/signin/login_ui_service.h
+++ b/chrome/browser/ui/webui/signin/login_ui_service.h
@@ -35,11 +35,14 @@ class LoginUIService : public KeyedService {
    public:
     // Called when a new login UI is shown.
     // |ui| The login UI that was just shown. Will never be null.
-    virtual void OnLoginUIShown(LoginUI* ui) = 0;
+    virtual void OnLoginUIShown(LoginUI* ui) {}
 
     // Called when a login UI is closed.
     // |ui| The login UI that was just closed; will never be null.
-    virtual void OnLoginUIClosed(LoginUI* ui) = 0;
+    virtual void OnLoginUIClosed(LoginUI* ui) {}
+
+    // Called when a confirmation UI for untrusted signin is shown.
+    virtual void UntrustedSigninUIShown() {}
 
    protected:
     virtual ~Observer() {}
@@ -65,6 +68,9 @@ class LoginUIService : public KeyedService {
   // sets current_login_ui() to null.
   void LoginUIClosed(LoginUI* ui);
 
+  // Called when a confirmation UI for untrusted signin is shown.
+  void UntrustedSigninUIShown();
+
   // Delegate to an existing login dialog if one exists.
   // If not, we make a new popup dialog window, and set it to
   // chrome://signin to ask the user to sign in to chrome.