Converted Observatory json-view element

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

Index: runtime/observatory/lib/src/app/application.dart
diff --git a/runtime/observatory/lib/src/app/application.dart b/runtime/observatory/lib/src/app/application.dart
index 1d13c9f19c26a616c56f81a99f9d985db7e5aa84..ea23d604fa59fd53017af2886c7d71028324b9b7 100644
--- a/runtime/observatory/lib/src/app/application.dart
+++ b/runtime/observatory/lib/src/app/application.dart
@@ -73,8 +73,6 @@ class ObservatoryApplication extends Observable {
 
   @reflectable final ObservatoryApplicationElement rootElement;
 
-  TraceViewElement _traceView = null;
-
   @reflectable ServiceObject lastErrorOrException;
 
   void _initOnce() {
@@ -139,9 +137,6 @@ class ObservatoryApplication extends Observable {
     if (Tracer.current != null) {
       Tracer.current.reset();
     }
-    if (_traceView != null) {
-      _traceView.tracer = Tracer.current;
-    }
     for (var i = 0; i < _pageRegistry.length; i++) {
       var page = _pageRegistry[i];
       if (page.canVisit(uri)) {
@@ -175,11 +170,6 @@ class ObservatoryApplication extends Observable {
     // Add new page.
     rootElement.children.add(page.element);
 
-    // Add tracing support.
-    _traceView = new Element.tag('trace-view');
-    _traceView.tracer = Tracer.current;
-    rootElement.children.add(_traceView);
-
     // Remember page.
     currentPage = page;
   }