make callbacks test work with SD polyfill.

Author: sorvell

test/html/callbacks.html

@@ -72,15 +72,18 @@
         ready: function() {
           this.stuff = [1, 2, 3];
           this.onMutation(this.$.container, function() {
-            var base = this.shadowRoot.querySelector('x-base');
-            chai.assert.isTrue(base.isReadied, 'template bind stamped element is ready');
-            chai.assert.isTrue(base.isInserted, 'template bind stamped element is enteredView');
-            var exts = this.shadowRoot.querySelectorAll('x-exendor');
-            for (var i=0, e; (i < exts.length) && (e = exts[i]); i++) {
-              chai.assert.isTrue(e.isReadied, 'template repeat stamped element is ready');
-              chai.assert.isTrue(e.isInserted, 'template repeat stamped element is enteredView');
-            }
-            done();
+            // TODO(sorvell): SD polyfill mutation observer ordering issue, file bug
+            setTimeout(function() {
+              var base = this.shadowRoot.querySelector('x-base');
+              chai.assert.isTrue(base.isReadied, 'template bind stamped element is ready');
+              chai.assert.isTrue(base.isInserted, 'template bind stamped element is enteredView');
+              var exts = this.shadowRoot.querySelectorAll('x-exendor');
+              for (var i=0, e; (i < exts.length) && (e = exts[i]); i++) {
+                chai.assert.isTrue(e.isReadied, 'template repeat stamped element is ready');
+                chai.assert.isTrue(e.isInserted, 'template repeat stamped element is enteredView');
+              }
+              done();
+            }.bind(this));
           });
         }
       });