Centralized event streams

runtime/observatory/lib/src/elements/nav/bar.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:html';
 import 'dart:async';
 import 'package:observatory/src/elements/helpers/tag.dart';
 import 'package:observatory/src/elements/helpers/rendering_scheduler.dart';
 
 class NavBarElement extends HtmlElement implements Renderable {
   static final StyleElement _style = () {
       var style = new StyleElement();
       style.text = 'nav.nav-bar {'
+                     'line-height: normal;'
                      'position: fixed;'
-                     'top: -56px;'
+                     'top: 0;'
                      'width: 100%;'
                      'z-index: 1000;'
                      '}'
                    'nav.nav-bar > ul {'
                      'display: inline-table;'
                      'position: relative;'
                      'list-style: none;'
                      'padding-left: 0;'
-                     'margin-left: 0;'
+                     'margin: 0;'
                      'width: 100%;'
                      'z-index: 1000;'
                      'font: 400 16px \'Montserrat\', sans-serif;'
                      'color: white;'
                      'background-color: #0489c3;'
-                   '}'
-                   'nav.nav-bar:after {'
-                     'content: ""; clear: both; display: block;'
-                   '}'
-                   'nav.nav-bar:before {'
-                     'height: 40px;'
-                     'background-color: #0489c3;'
-                     'content: ""; display: block;'
                    '}';
       return style;
   }();
 
   static const tag = const Tag<NavBarElement>('nav-bar');
 
   RenderingScheduler _r;
 
   Stream<RenderedEvent<NavBarElement>> get onRendered => _r.onRendered;
 
@@ skipping 26 matching lines @@
         ..children = [
           new UListElement()
             ..children = [
               new ContentElement()
             ],
         ],
       new DivElement()
     ];
   }
 }