Port sky-drawer to Dart

Also, port the "appish" example to exercise the drawer.

R=eseidel@chromium.org

Review URL: https://codereview.chromium.org/942413002

examples/example-scaffold.sky → examples/appish/example-scaffold.sky

@@ -4,10 +4,10 @@
 // found in the LICENSE file.
 -->
 <import src="/sky/framework/sky-drawer.sky" />
-<import src="/sky/framework/sky-element/sky-element.sky" as="SkyElement" />
+<import src="/sky/framework/sky-element.sky" />
 <import src="/sky/framework/sky-scrollable.sky" />
 
-<sky-element name="example-scaffold">
+<sky-element>
 <template>
   <style>
     :host {
@@ -54,7 +54,7 @@
     <content select=".menu"/>
   </sky-drawer>
   <sky-toolbar>
-    <div id="menu" on-click="handleMenuClick"/>
+    <div id="menu" />
     <content id="title" select=".title"/>
   </sky-toolbar>
   <sky-scrollable>
@@ -62,18 +62,23 @@
   </sky-scrollable>
 </template>
 <script>
-module.exports = class extends SkyElement {
-  created() {
-    this.toolbar_ = null;
-  }
+import "dart:sky";
+
+@Tagname('example-scaffold')
+class ExampleScaffold extends SkyElement {
+  Element _drawer;
 
-  shadowRootReady() {
-    this.toolbar_ = this.shadowRoot.getElementById('drawer');
+  void shadowRootReady() {
+    _drawer = shadowRoot.getElementById('drawer');
+    Element menu = shadowRoot.getElementById('menu');
+    menu.addEventListener('click', _handleMenuClick);
   }
 
-  handleMenuClick() {
-    this.toolbar_.toggle();
+  void _handleMenuClick(_) {
+    _drawer.toggle();
   }
-}.register();
+}
+
+_init(script) => register(script, ExampleScaffold);
 </script>
 </sky-element>

examples/appish.sky → examples/appish/index.sky

@@ -4,23 +4,9 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 -->
-<sky>
-<import src="/sky/framework/sky-element/sky-element.sky" as="SkyElement" />
 <import src="example-scaffold.sky" />
-
-<sky-element name="example-app">
-<template>
-  <example-scaffold>
+<example-scaffold>
   <div class="title">Awesome app</div>
   <div class="menu">This is a menu</div>
   <div class="body">This is an awesome app.</div>
-  </example-scrollable>
-</template>
-<script>
-module.exports = class extends SkyElement {
-}.register();
-</script>
-</sky-element>
-
-<example-app />
-</sky>
+</example-scrollable>