Delete drawerController and make drawer handle back behavior natively

sky/sdk/example/fitness/lib/home.dart

Index: sky/sdk/example/fitness/lib/home.dart
diff --git a/sky/sdk/example/fitness/lib/home.dart b/sky/sdk/example/fitness/lib/home.dart
index c22a80fb12876a55c4dc17362b6750aa3f6412f8..d78678e1f49d1f3ea8720ca2da91492c232e26aa 100644
--- a/sky/sdk/example/fitness/lib/home.dart
+++ b/sky/sdk/example/fitness/lib/home.dart
@@ -31,13 +31,6 @@ class HomeFragment extends StatefulComponent {
 
   FitnessMode _fitnessMode = FitnessMode.measure;
 
-  void initState {
-    // if (debug)
-    //   new Timer(new Duration(seconds: 1), dumpState);
-    _drawerController = new DrawerController(_handleDrawerStatusChanged);
-    super.initState();
-  }
-
   void syncFields(HomeFragment source) {
     navigator = source.navigator;
     userData = source.userData;
@@ -46,30 +39,20 @@ class HomeFragment extends StatefulComponent {
   bool _isShowingSnackBar = false;
   bool _isRunning = false;
 
-  DrawerController _drawerController;
   bool _drawerShowing = false;
 
-  void _handleDrawerStatusChanged(bool showing) {
-    if (!showing && navigator.currentRoute.name == "/drawer") {
-      navigator.pop();
-    }
-    setState(() {
-      _drawerShowing = showing;
-    });
-  }
-
   void _handleFitnessModeChange(FitnessMode value) {
     setState(() {
       _fitnessMode = value;
     });
-    assert(navigator.currentRoute.name == '/drawer');
-    navigator.pop();
   }
 
   Drawer buildDrawer() {
     return new Drawer(
-      controller: _drawerController,
+      showing: _drawerShowing,
       level: 3,
+      onStatusChange: _handleDrawerStatusChange,
+      navigator: navigator,
       children: [
         new DrawerHeader(children: [new Text('Fitness')]),
         new MenuItem(
@@ -94,17 +77,20 @@ class HomeFragment extends StatefulComponent {
     );
   }
 
+  void _handleDrawerStatusChange(bool showing) {
+    setState(() {
+      _drawerShowing = showing;
+    });
+  }
+
   void _handleShowSettings() {
-    assert(navigator.currentRoute.name == '/drawer');
     navigator.pop();
-    assert(navigator.currentRoute.name == '/');
     navigator.pushNamed('/settings');
   }
 
   void _handleOpenDrawer() {
-    _drawerController.open();
-    navigator.pushState("/drawer", (_) {
-      _drawerController.close();
+    setState(() {
+      _drawerShowing = true;
     });
   }
 
@@ -203,7 +189,7 @@ class HomeFragment extends StatefulComponent {
       body: buildBody(),
       snackBar: buildSnackBar(),
       floatingActionButton: buildFloatingActionButton(),
-      drawer: _drawerShowing ? buildDrawer() : null
+      drawer: buildDrawer()
     );
   }
 }