Redo LocationManager to use HTML5 History API

runtime/bin/vmservice/client/lib/src/elements/observatory_element.dart

Index: runtime/bin/vmservice/client/lib/src/elements/observatory_element.dart
diff --git a/runtime/bin/vmservice/client/lib/src/elements/observatory_element.dart b/runtime/bin/vmservice/client/lib/src/elements/observatory_element.dart
index b88955911dee7bb14cb924c0bcc78f6e8699344c..55adba45af4611f08a87e109a9c338a11acf9f68 100644
--- a/runtime/bin/vmservice/client/lib/src/elements/observatory_element.dart
+++ b/runtime/bin/vmservice/client/lib/src/elements/observatory_element.dart
@@ -4,6 +4,7 @@
 
 library observatory_element;
 
+import 'dart:html';
 import 'package:observatory/app.dart';
 import 'package:polymer/polymer.dart';
 
@@ -24,6 +25,14 @@ class ObservatoryElement extends PolymerElement {
     super.ready();
   }
 
+  void goto(MouseEvent event, var detail, Element target) {
+    location.onGoto(event, detail, target);
+  }
+
+  String gotoLink(String url) {
+    return location.makeLink(url);
+  }
+
   void attributeChanged(String name, var oldValue, var newValue) {
     super.attributeChanged(name, oldValue, newValue);
   }