Use dartfmt on Observatory code

runtime/observatory/lib/src/elements/megamorphiccache_ref.dart

 // Copyright (c) 2013, 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/models.dart' as M
-  show IsolateRef, MegamorphicCacheRef;
+    show IsolateRef, MegamorphicCacheRef;
 import 'package:observatory/src/elements/helpers/rendering_scheduler.dart';
 import 'package:observatory/src/elements/helpers/tag.dart';
 import 'package:observatory/src/elements/helpers/uris.dart';
 
 class MegamorphicCacheRefElement extends HtmlElement implements Renderable {
   static const tag =
       const Tag<MegamorphicCacheRefElement>('megamorphic-cache-ref');
 
   RenderingScheduler<MegamorphicCacheRefElement> _r;
 
   Stream<RenderedEvent<MegamorphicCacheRefElement>> get onRendered =>
       _r.onRendered;
 
   M.IsolateRef _isolate;
   M.MegamorphicCacheRef _cache;
 
   M.IsolateRef get isolate => _isolate;
   M.MegamorphicCacheRef get cache => _cache;
 
-  factory MegamorphicCacheRefElement(M.IsolateRef isolate,
-      M.MegamorphicCacheRef cache, {RenderingQueue queue}) {
+  factory MegamorphicCacheRefElement(
+      M.IsolateRef isolate, M.MegamorphicCacheRef cache,
+      {RenderingQueue queue}) {
     assert(isolate != null);
     assert(cache != null);
     MegamorphicCacheRefElement e = document.createElement(tag.name);
     e._r = new RenderingScheduler(e, queue: queue);
     e._isolate = isolate;
     e._cache = cache;
     return e;
   }
 
   MegamorphicCacheRefElement.created() : super.created();
 
   @override
   void attached() {
     super.attached();
     _r.enable();
   }
 
   @override
   void detached() {
     super.detached();
     _r.disable(notify: true);
     children = [];
   }
 
   void render() {
     children = [
       new AnchorElement(href: Uris.inspect(_isolate, object: _cache))
         ..children = [
-          new SpanElement()..classes = ['emphasize']
+          new SpanElement()
+            ..classes = ['emphasize']
             ..text = 'MegarmorphicCache',
           new SpanElement()..text = ' (${_cache.selector})'
         ]
     ];
   }
 }