Begin implementing a debugger page in Observatory.

runtime/bin/vmservice/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 82 matching lines @@
         break;
 
       default:
         // Ignore unrecognized events.
         Logger.root.severe('Unrecognized event: $event');
         break;
     }
   }
 
   void _registerPages() {
-    // Register ClassTreePage.
     _pageRegistry.add(new ClassTreePage(this));
+    _pageRegistry.add(new DebuggerPage(this));
     _pageRegistry.add(new VMConnectPage(this));
     _pageRegistry.add(new ErrorViewPage(this));
     _pageRegistry.add(new MetricsPage(this));
     // Note that ServiceObjectPage must be the last entry in the list as it is
     // the catch all.
     _pageRegistry.add(new ServiceObjectPage(this));
   }
 
   void _onError(ServiceError error) {
     lastErrorOrException = error;
@@ skipping 102 matching lines @@
 
   _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());
   }
 }