Centralized event streams

runtime/observatory/lib/src/elements/source_link_wrapper.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/app.dart';
 import 'package:observatory/repositories.dart' show ScriptRepository;
 import 'package:observatory/service_html.dart' show SourceLocation;
 import 'package:observatory/src/elements/source_link.dart';
 import 'package:observatory/src/elements/helpers/tag.dart';
 import 'package:observatory/src/elements/shims/binding.dart';
 
 @bindable
 class SourceLinkElementWrapper extends HtmlElement {
   static const binder = const Binder<SourceLinkElementWrapper>(const {
       'location' : #location
     });
 
   static const tag = const Tag<SourceLinkElementWrapper>('source-link');
 
   SourceLocation _location;
   SourceLocation get location => location;
-  set location(SourceLocation location) { _location = location; render(); }
+  set location(SourceLocation value) {
+    _location = value;
+    render();
+  }
 
   SourceLinkElementWrapper.created() : super.created() {
     binder.registerCallback(this);
     createShadowRoot();
     render();
   }
 
   @override
   void attached() {
     super.attached();
     render();
   }
 
   Future render() async {
     shadowRoot.children = [];
-    if (_location == null) return;
+    if (_location == null) {
+      return;
+    }
 
     ScriptRepository repository = new ScriptRepository(_location.isolate);
 
     shadowRoot.children = [
       new StyleElement()
         ..text = '''
         source-link-wrapped > a[href]:hover {
             text-decoration: underline;
         }
         source-link-wrapped > a[href] {
             color: #0489c3;
             text-decoration: none;
         }''',
       new SourceLinkElement(_location.isolate, _location, repository,
                             queue: ObservatoryApplication.app.queue)
     ];
   }
 }