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

Source/core/workers/WorkerMessagingProxy.cpp

 /*
  * Copyright (C) 2008 Apple Inc. All Rights Reserved.
  * Copyright (C) 2009 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:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
@@ skipping 30 matching lines @@
 #include "core/inspector/WorkerInspectorController.h"
 #include "core/loader/DocumentLoadTiming.h"
 #include "core/loader/DocumentLoader.h"
 #include "core/workers/DedicatedWorkerGlobalScope.h"
 #include "core/workers/DedicatedWorkerThread.h"
 #include "core/workers/Worker.h"
 #include "core/workers/WorkerClients.h"
 #include "core/workers/WorkerObjectProxy.h"
 #include "core/workers/WorkerThreadStartupData.h"
 #include "platform/NotImplemented.h"
+#include "platform/TraceEvent.h"
 #include "platform/heap/Handle.h"
 #include "wtf/Functional.h"
 #include "wtf/MainThread.h"
 
 namespace blink {
 
 class MessageWorkerGlobalScopeTask : public ExecutionContextTask {
 public:
     static PassOwnPtr<MessageWorkerGlobalScopeTask> create(PassRefPtr<SerializedScriptValue> message, PassOwnPtr<MessagePortChannelArray> channels)
     {
@@ skipping 185 matching lines @@
 }
 
 void WorkerMessagingProxy::sendMessageToInspector(const String& message)
 {
     if (m_askedToTerminate)
         return;
     m_workerThread->postDebuggerTask(createCrossThreadTask(dispatchOnInspectorBackendTask, String(message)));
     m_workerThread->interruptAndDispatchInspectorCommands();
 }
 
+static void dispatchWriteTimelineStartedEvent(ExecutionContext* context, const String& sessionId)
+{
+    TRACE_EVENT_INSTANT1(TRACE_DISABLED_BY_DEFAULT("devtools.timeline"), "TracingStartedInWorker", "sessionId", sessionId.utf8());
+}
+
+void WorkerMessagingProxy::writeTimelineStartedEvent(const String& sessionId)
+{
+    if (m_askedToTerminate)
+        return;
+    OwnPtr<ExecutionContextTask> task = createCrossThreadTask(dispatchWriteTimelineStartedEvent, String(sessionId));
+    if (m_workerThread)
+        m_workerThread->postTask(task.release());
+    else
+        m_queuedEarlyTasks.append(task.release());
+}
+
 void WorkerMessagingProxy::workerGlobalScopeDestroyed()
 {
     // This method is always the last to be performed, so the proxy is not needed for communication
     // in either side any more. However, the Worker object may still exist, and it assumes that the proxy exists, too.
     m_askedToTerminate = true;
     m_workerThread = nullptr;
 
     InspectorInstrumentation::workerGlobalScopeTerminated(m_executionContext.get(), this);
 
     if (m_mayBeDestroyed)
@@ skipping 31 matching lines @@
 {
     m_workerThreadHadPendingActivity = hasPendingActivity;
 }
 
 bool WorkerMessagingProxy::hasPendingActivity() const
 {
     return (m_unconfirmedMessageCount || m_workerThreadHadPendingActivity) && !m_askedToTerminate;
 }
 
 } // namespace blink