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 385 matching lines @@
 
   void onInstall() {
     if (element == null) {
       element = container;
     }
     assert(element != null);
   }
 
   @override
   void onUninstall() {
-    assert(element != null);
-    element.children = const [];
+    super.onUninstall();
+    container.children = const [];
   }
 }
 
 class ObjectStorePage extends MatchingPage {
   ObjectStorePage(app) : super('object-store', app);
 
   final DivElement container = new DivElement();
 
   void _visit(Uri uri) {
     super._visit(uri);
@@ skipping 81 matching lines @@
     });
   }
 
   void onInstall() {
     if (element == null) {
       element = container;
     }
     app.startGCEventListener();
   }
 
+  @override
   void onUninstall() {
     super.onUninstall();
     app.stopGCEventListener();
+    container.children = const [];
   }
 }
 
 class PortsPage extends MatchingPage {
   PortsPage(app) : super('ports', app);
 
   final DivElement container = new DivElement();
 
   void _visit(Uri uri) {
     super._visit(uri);
@@ skipping 89 matching lines @@
 
   @override
   void onInstall() {
     element = container;
     container.children = const [];
     app.startLoggingEventListener();
   }
 
   @override
   void onUninstall() {
+    super.onUninstall();
+    container.children = const [];
     app.stopLoggingEventListener();
   }
 
   void _visit(Uri uri) {
     assert(element != null);
     assert(canVisit(uri));
     getIsolate(uri).then((isolate) {
       container.children = [
         new LoggingPageElement(app.vm, isolate, app.events,
                                app.notifications, queue: app.queue)
@@ skipping 87 matching lines @@
   }
 
   void onInstall() {
     if (element == null) {
       element = container;
     }
   }
 
   @override
   void onUninstall() {
+    super.onUninstall();
     _metricRepository.stopSampling(lastIsolate);
+    container.children = const [];
   }
 }
 
 class TimelinePage extends Page {
   TimelinePage(app) : super(app);
 
   void onInstall() {
     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';
 }