Reverting setTimeout removal.

samples/swarm/swarm_ui_lib/view/ConveyorView.dart

Index: samples/swarm/swarm_ui_lib/view/ConveyorView.dart
diff --git a/samples/swarm/swarm_ui_lib/view/ConveyorView.dart b/samples/swarm/swarm_ui_lib/view/ConveyorView.dart
index 87c0710af71221fba597e13611af7e1ce532a88f..696c1bd4d74c3ad3c843f3c33b93e31e9bbedcad 100644
--- a/samples/swarm/swarm_ui_lib/view/ConveyorView.dart
+++ b/samples/swarm/swarm_ui_lib/view/ConveyorView.dart
@@ -23,11 +23,11 @@ class ConveyorView extends CompositeView {
   // which view is selected? (e.g. the MVVM pattern)
   Function viewSelected;
 
-  Timer animationTimer;
+  int animationTimeoutId;
 
   ConveyorView()
   : super('conveyor-view', true),
-    animationTimer = null {
+    animationTimeoutId = null {
   }
 
   Element render() {
@@ -61,10 +61,13 @@ class ConveyorView extends CompositeView {
     final xTranslationPercent = -index * 100;
     style.transform = 'translate3d(${xTranslationPercent}%, 0px, 0px)';
 
+    if (animationTimeoutId != null) {
+      window.clearTimeout(animationTimeoutId);
+    }
+
     if (animate) {
-      animationTimer = new Timer(
-          new Duration(milliseconds: ((durationSeconds * 1000).toInt())),
-          () { _onAnimationEnd(); });
+      animationTimeoutId = window.setTimeout(
+          () { _onAnimationEnd(); }, (durationSeconds * 1000).toInt());
     }
     // TODO(mattsh), we should set the visibility to hide everything but the
     // selected view.