Removed polymer & mirror from Observatory

runtime/observatory/lib/src/app/page.dart

 // Copyright (c) 2014, 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;
 
 final _allocationProfileRepository = new AllocationProfileRepository();
 final _breakpointRepository = new BreakpointRepository();
 final _classSampleProfileRepository = new ClassSampleProfileRepository();
 final _classRepository = new ClassRepository();
@@ skipping 30 matching lines @@
 RetainedSizeRepository _retainedSizeRepository = new RetainedSizeRepository();
 ReachableSizeRepository _reachableSizeRepository
     = new ReachableSizeRepository();
 RetainingPathRepository _retainingPathRepository
     = new RetainingPathRepository();
 
 /// A [Page] controls the user interface of Observatory. At any given time
 /// one page will be the current page. Pages are registered at startup.
 /// When the user navigates within the application, each page is asked if it
 /// can handle the current location, the first page to say yes, wins.
-abstract class Page extends Observable {
+abstract class Page {
   final ObservatoryApplication app;
-  final ObservableMap<String, String> internalArguments =
-      new ObservableMap<String, String>();
-  @observable HtmlElement element;
+  final Map<String, String> internalArguments = <String, String>{};
+  HtmlElement element;
 
   Page(this.app);
 
   /// Called when the page is installed, this callback must initialize
   /// [element].
   void onInstall();
 
   /// Called when the page is uninstalled, this callback must clear
   /// [element].
   void onUninstall() {
@@ skipping 725 matching lines @@
     element = new TimelinePageElement(app.vm, app.events, app.notifications,
                                       queue: app.queue);
   }
 
   void _visit(Uri uri) {
     assert(canVisit(uri));
   }
 
   bool canVisit(Uri uri) => uri.path == 'timeline';
 }