Remove outdated hack from flights-app

sky/examples/flights-app/index.sky

Index: sky/examples/flights-app/index.sky
diff --git a/sky/examples/flights-app/index.sky b/sky/examples/flights-app/index.sky
index 9f262528d3f9c386d7aa8ab53432531c42c3b0ea..31c55af1efb61923bd75273bbb57a0ce8c882c34 100644
--- a/sky/examples/flights-app/index.sky
+++ b/sky/examples/flights-app/index.sky
@@ -5,11 +5,5 @@
       height: 100%;
     }
   </style>
-  <script>
-    // TODO(esprehn): Work around a bug where having <flights-app /> in the
-    // page doesn't render anything until the first input event.
-    window.addEventListener("load", function() {
-      document.querySelector("sky").appendChild(new FlightsAppElement());
-    });
-  </script>
+  <flights-app />
 </sky>