Fix gr-registration-dialog test failure in Safari

Wrap test in flush because we use dom-repeat for email options.

Change-Id: I57bde19a4db66aec0ffb09cd08fa6584b972369a
diff --git a/polygerrit-ui/app/elements/settings/gr-registration-dialog/gr-registration-dialog_test.html b/polygerrit-ui/app/elements/settings/gr-registration-dialog/gr-registration-dialog_test.html
index 0b9dc9c..33f6aed 100644
--- a/polygerrit-ui/app/elements/settings/gr-registration-dialog/gr-registration-dialog_test.html
+++ b/polygerrit-ui/app/elements/settings/gr-registration-dialog/gr-registration-dialog_test.html
@@ -119,18 +119,20 @@
     });
 
     test('saves name and preferred email', function(done) {
-      element.$.name.value = 'new name';
-      element.$.email.value = 'email3';
+      flush(function() {
+        element.$.name.value = 'new name';
+        element.$.email.value = 'email3';
 
-      // Nothing should be committed yet.
-      assert.equal(account.name, 'name');
-      assert.equal(account.email, 'email');
+        // Nothing should be committed yet.
+        assert.equal(account.name, 'name');
+        assert.equal(account.email, 'email');
 
-      // Save and verify new values are committed.
-      save().then(function() {
-        assert.equal(account.name, 'new name');
-        assert.equal(account.email, 'email3');
-      }).then(done);
+        // Save and verify new values are committed.
+        save().then(function() {
+          assert.equal(account.name, 'new name');
+          assert.equal(account.email, 'email3');
+        }).then(done);
+      });
     });
 
     test('pressing enter saves name', function(done) {