Small refactor of pages

runtime/observatory/lib/src/app/application.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.
 
 part of app;
 
 /// The observatory application. Instances of this are created and owned
 /// by the observatory_application custom element.
 class ObservatoryApplication extends Observable {
   static ObservatoryApplication app;
@@ skipping 177 matching lines @@
 
     // Add tracing support.
     _traceView = new Element.tag('trace-view');
     _traceView.tracer = Tracer.current;
     rootElement.children.add(_traceView);
 
     // Remember page.
     currentPage = page;
   }
 
-  ObservatoryApplication.devtools(this.rootElement) :
-      locationManager = new HashLocationManager(),
-      targets = null {
-    vm = new PostMessageVM();
-    _initOnce(true);
-  }
-
   ObservatoryApplication(this.rootElement) :
       locationManager = new HashLocationManager(),
       targets = new TargetManager() {
     vm = new WebSocketVM(targets.defaultTarget);
     _initOnce(false);
   }
 
   void _removeDisconnectEvents() {
     notifications.removeWhere((oldEvent) {
         return (oldEvent.eventType == 'VMDisconnected');
       });
   }
 
   _vmConnected(VM vm) {
     if (vm is WebSocketVM) {
       targets.add(vm.target);
     }
     _removeDisconnectEvents();
   }
 
   _vmDisconnected(VM vm) {
     if (this.vm != vm) {
       // This disconnect event occured *after* a new VM was installed.
       return;
     }
     this.vm = null;
     notifications.add(new ServiceEvent.vmDisconencted());
   }
 }