Record DevTools metadata events on worker threads when starting recoring tracing based Timeline

Source/core/inspector/InspectorWorkerAgent.cpp

 /*
  * Copyright (C) 2011 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 181 matching lines @@
         channel->proxy()->sendMessageToInspector(message->toJSONString());
     else
         *error = "Worker is gone";
 }
 
 void InspectorWorkerAgent::setAutoconnectToWorkers(ErrorString*, bool value)
 {
     m_state->setBoolean(WorkerAgentState::autoconnectToWorkers, value);
 }
 
+void InspectorWorkerAgent::setTracingSessionId(const String& sessionId)
+{
+    m_tracingSessionId = sessionId;
+    if (sessionId.isEmpty())
+        return;
+    for (DedicatedWorkers::iterator it = m_dedicatedWorkers.begin(); it != m_dedicatedWorkers.end(); ++it)
+        it->key->writeTimelineStartedEvent(sessionId);
+}
+
 bool InspectorWorkerAgent::shouldPauseDedicatedWorkerOnStart()
 {
     return m_state->getBoolean(WorkerAgentState::autoconnectToWorkers);
 }
 
 void InspectorWorkerAgent::didStartWorkerGlobalScope(WorkerGlobalScopeProxy* workerGlobalScopeProxy, const KURL& url)
 {
     m_dedicatedWorkers.set(workerGlobalScopeProxy, url.string());
     if (m_inspectorFrontend && m_state->getBoolean(WorkerAgentState::workerInspectionEnabled))
         createWorkerFrontendChannel(workerGlobalScopeProxy, url.string());
+    if (!m_tracingSessionId.isEmpty())
+        workerGlobalScopeProxy->writeTimelineStartedEvent(m_tracingSessionId);
 }
 
 void InspectorWorkerAgent::workerGlobalScopeTerminated(WorkerGlobalScopeProxy* proxy)
 {
     m_dedicatedWorkers.remove(proxy);
     for (WorkerChannels::iterator it = m_idToChannel.begin(); it != m_idToChannel.end(); ++it) {
         if (proxy == it->value->proxy()) {
             m_inspectorFrontend->worker()->workerTerminated(it->key);
             delete it->value;
             m_idToChannel.remove(it);
@@ skipping 23 matching lines @@
     m_idToChannel.set(channel->id(), channel);
 
     ASSERT(m_inspectorFrontend);
     bool autoconnectToWorkers = m_state->getBoolean(WorkerAgentState::autoconnectToWorkers);
     if (autoconnectToWorkers)
         channel->connectToWorkerGlobalScope();
     m_inspectorFrontend->worker()->workerCreated(channel->id(), url, autoconnectToWorkers);
 }
 
 } // namespace blink