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

runtime/vm/service_event.h

 // Copyright (c) 2015, 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.
 
 #ifndef VM_SERVICE_EVENT_H_
 #define VM_SERVICE_EVENT_H_
 
 #include "vm/debugger.h"
 
 class DebuggerEvent;
 
 namespace dart {
 
 class ServiceEvent {
  public:
   enum EventKind {
     kIsolateStart,       // New isolate has started
+    kIsolateRunnable,    // Isolate is ready to run
     kIsolateExit,        // Isolate has exited
     kIsolateUpdate,      // Isolate identity information has changed
 
     kPauseStart,         // --pause-isolates-on-start
     kPauseExit,          // --pause-isolates-on-exit
     kPauseBreakpoint,
     kPauseInterrupted,
     kPauseException,
     kResume,
     kBreakpointAdded,
@@ skipping 152 matching lines @@
   const Object* inspectee_;
   const Heap::GCStats* gc_stats_;
   const uint8_t* bytes_;
   intptr_t bytes_length_;
   LogRecord log_record_;
 };
 
 }  // namespace dart
 
 #endif  // VM_SERVICE_EVENT_H_