fix(tests): disable shadowDom in examples until chromedriver support is available

Author: chirayuk

example/web/animation/repeat_demo.dart

@@ -2,7 +2,7 @@ part of animation;
 
 @Component(
     selector: 'repeat-demo',
-    useShadowDom: true,
+    useShadowDom: false,
     template: '''
       <div class="repeat-demo">
       <button ng-click="ctrl.addItem()">Add Thing</button>

example/web/animation/visibility_demo.dart

@@ -16,7 +16,8 @@ part of animation;
       </div>
       </div>
     ''',
-    publishAs: 'ctrl')
+    publishAs: 'ctrl',
+    useShadowDom: false)
 class VisibilityDemo {
   bool visible = false;
 }