Adds error handling in the signin handler when fetchProvidersForEmail… (#123)

* Adds error handling in the signin handler when fetchProvidersForEmail throws some error.
This was noticed when the email entered passes client validation but fails on backend
validation. In that case, we should display and info bar with the backend error.

* Fixes minor version for closure builder. Latest version is breaking in Travis integration tests.

* Revert previous closure builder version change.

Author: bojeil-google

javascript/widgets/handler/common.js

@@ -887,7 +887,14 @@ firebaseui.auth.widget.handler.common.handleStartEmailFirstFlow =
                 undefined,
                 opt_infoBarMessage);
       },
-      function(error) {}
+      function(error) {
+        // The email provided could be an invalid one or some other error
+        // could occur.
+        var errorMessage =
+            firebaseui.auth.widget.handler.common.getErrorMessage(
+                error);
+        component.showInfoBar(errorMessage);
+      }
   ));
 };
 

javascript/widgets/handler/signin_test.js

@@ -77,6 +77,42 @@ function testHandleSignIn() {
 }
 
 
+function testHandleSignIn_accountLookupError() {
+  // Test when account lookup throws an error.
+  var expectedError = {
+    'code': 'auth/invalid-email',
+    'message': 'The email address is badly formatted.'
+  };
+  app.updateConfig('signInOptions', signInOptionsWithScopes);
+  firebaseui.auth.widget.handler.handleSignIn(app, container);
+  assertSignInPage();
+
+  // Now email input has 'user', which is not a valid email address.
+  var emailInput = getEmailElement();
+  // Pass an invalid email that will pass client side validation.
+  goog.dom.forms.setValue(emailInput, 'me.@google.com');
+  goog.testing.events.fireKeySequence(emailInput, goog.events.KeyCodes.ENTER);
+  assertSignInPage();
+
+  // Enter key triggers fetchProvidersForEmail.
+  goog.testing.events.fireKeySequence(emailInput, goog.events.KeyCodes.ENTER);
+
+  testAuth.assertFetchProvidersForEmail(
+      ['me.@google.com'],
+      null,
+      expectedError);
+  return testAuth.process().then(function() {
+    // Should remain on the same page.
+    assertSignInPage();
+    // Account should not be remembered.
+    assertFalse(firebaseui.auth.storage.isRememberAccount(app.getAppId()));
+    // Error message should be displayed in the info bar.
+    assertInfoBarMessage(
+        firebaseui.auth.widget.handler.common.getErrorMessage(expectedError));
+  });
+}
+
+
 function testHandleSignIn_reset() {
   // Test when reset is called after sign-in handler called.
   firebaseui.auth.widget.handler.handleSignIn(app, container);