Miscellaneous Observatory UI improvements

runtime/vm/isolate.cc

 // 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.
 
 #include "vm/isolate.h"
 
 #include "include/dart_api.h"
 #include "platform/assert.h"
 #include "platform/json.h"
 #include "lib/mirrors.h"
@@ skipping 908 matching lines @@
   jsobj.AddProperty("livePorts", live_ports);
   jsobj.AddProperty("controlPorts", control_ports);
   jsobj.AddProperty("pausedOnStart", pause_on_start);
   jsobj.AddProperty("pausedOnExit", paused_on_exit);
   jsobj.AddProperty("pauseOnExit", pause_on_exit);
   const Library& lib =
       Library::Handle(object_store()->root_library());
   jsobj.AddProperty("rootLib", lib);
 
   timer_list().PrintTimersToJSONProperty(&jsobj);
-
+  {
+    JSONObject tagCounters(&jsobj, "tagCounters");
+    vm_tag_counters()->PrintToJSONObject(&tagCounters);
+  }
   if (object_store()->sticky_error() != Object::null()) {
     Error& error = Error::Handle(this, object_store()->sticky_error());
     ASSERT(!error.IsNull());
     jsobj.AddProperty("error", error, false);
   }
 
   {
     JSONObject typeargsRef(&jsobj, "canonicalTypeArguments");
     typeargsRef.AddProperty("type", "@TypeArgumentsList");
     typeargsRef.AddProperty("id", "typearguments");
@@ skipping 181 matching lines @@
   return func.raw();
 }
 
 
 void IsolateSpawnState::Cleanup() {
   SwitchIsolateScope switch_scope(isolate());
   Dart::ShutdownIsolate();
 }
 
 }  // namespace dart