Converted Observatory cpu-profile element

runtime/observatory/lib/src/elements/helpers/rendering_scheduler.dart

 // Copyright (c) 2016, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 import 'dart:async';
 
 import 'package:observatory/src/elements/helpers/rendering_queue.dart';
 export 'package:observatory/src/elements/helpers/rendering_queue.dart';
 
 /// A generic renderable object.
 abstract class Renderable {
   void render();
 }
 
 /// Event related to a Renderable rendering phase.
-class RenderedEvent<T extends Renderable> {
+class RenderedEvent<T> {
   /// Renderable to which the event is related
   final T element;
   /// Is another rendering scheduled for this element.
   final bool otherRenderScheduled;
 
   RenderedEvent(this.element, this.otherRenderScheduled) {
     assert(element != null);
     assert(otherRenderScheduled != null);
   }
 }
@@ skipping 85 matching lines @@
     if (_notificationScheduled) return;
     _notify();
     _notificationScheduled = true;
   }
 
   Future _notify() async {
     _onRendered.add(new RenderedEvent<T>(element, _dirty));
     _notificationScheduled = false;
   }
 }