Add ASSERT(isMainThread()) to WorkerThread::start() and ::terminate()

Source/core/workers/WorkerThread.cpp

 /*
  * Copyright (C) 2008 Apple 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
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 159 matching lines @@
 
 WorkerThread::~WorkerThread()
 {
     MutexLocker lock(threadSetMutex());
     ASSERT(workerThreads().contains(this));
     workerThreads().remove(this);
 }
 
 void WorkerThread::start(PassOwnPtr<WorkerThreadStartupData> startupData)
 {
+    ASSERT(isMainThread());
+
     if (m_started)
         return;
 
     m_started = true;
     backingThread().postTask(FROM_HERE, new Task(threadSafeBind(&WorkerThread::initialize, AllowCrossThreadAccess(this), startupData)));
 }
 
 void WorkerThread::interruptAndDispatchInspectorCommands()
 {
     MutexLocker locker(m_workerInspectorControllerMutex);
@@ skipping 110 matching lines @@
 }
 
 bool WorkerThread::terminated()
 {
     MutexLocker lock(m_threadStateMutex);
     return m_terminated;
 }
 
 void WorkerThread::terminateInternal()
 {
+    ASSERT(isMainThread());
+
     // Protect against this method, initialize() or termination via the global scope racing each other.
     MutexLocker lock(m_threadStateMutex);
 
     // If terminateInternal has already been called, just return.
     if (m_terminated)
         return;
     m_terminated = true;
 
     // Signal the thread to notify that the thread's stopping.
     if (m_shutdownEvent)
@@ skipping 163 matching lines @@
     InspectorInstrumentation::didLeaveNestedRunLoop(m_workerGlobalScope.get());
 }
 
 void WorkerThread::setWorkerInspectorController(WorkerInspectorController* workerInspectorController)
 {
     MutexLocker locker(m_workerInspectorControllerMutex);
     m_workerInspectorController = workerInspectorController;
 }
 
 } // namespace blink