Add an IsolateRunnable event to the service protocol. Improve service docs.

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 "vm/code_observers.h"
@@ skipping 997 matching lines @@
     ASSERT(this == state->isolate());
     Run();
   }
   TimelineStream* stream = GetIsolateStream();
   ASSERT(stream != NULL);
   TimelineEvent* event = stream->StartEvent();
   if (event != NULL) {
     event->Instant("Runnable");
     event->Complete();
   }
+  if (Service::isolate_stream.enabled()) {
+    ServiceEvent runnableEvent(this, ServiceEvent::kIsolateRunnable);
+    Service::HandleEvent(&runnableEvent);
+  }
   return true;
 }
 
 
 bool Isolate::VerifyPauseCapability(const Object& capability) const {
   return !capability.IsNull() &&
       capability.IsCapability() &&
       (pause_capability() == Capability::Cast(capability).Id());
 }
 
@@ skipping 669 matching lines @@
     // TODO(turnidge): Don't compute a full stack trace.
     DebuggerStackTrace* stack = debugger()->StackTrace();
     if (stack->Length() > 0) {
       pause_event.set_top_frame(stack->FrameAt(0));
     }
     jsobj.AddProperty("pauseEvent", &pause_event);
   }
 
   const Library& lib =
       Library::Handle(object_store()->root_library());
-  jsobj.AddProperty("rootLib", lib);
+  if (!lib.IsNull()) {
+    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);
@@ skipping 428 matching lines @@
                            serialized_message_, serialized_message_len_);
 }
 
 
 void IsolateSpawnState::Cleanup() {
   SwitchIsolateScope switch_scope(I);
   Dart::ShutdownIsolate();
 }
 
 }  // namespace dart