Initializes the context of WorkerScriptController before calling willEvaluateWorkerScript.

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 110 matching lines @@
         }
     }
     // The corresponding call to didStopWorkerRunLoop is in
     // ~WorkerScriptController.
     blink::Platform::current()->didStartWorkerRunLoop(blink::WebWorkerRunLoop(&m_runLoop));
 
     // Notify proxy that a new WorkerGlobalScope has been created and started.
     m_workerReportingProxy.workerGlobalScopeStarted(m_workerGlobalScope.get());
 
     WorkerScriptController* script = m_workerGlobalScope->script();
+    if (!script->isExecutionForbidden())
+        script->initializeContextIfNeeded();
     InspectorInstrumentation::willEvaluateWorkerScript(workerGlobalScope(), startMode);
     script->evaluate(ScriptSourceCode(sourceCode, scriptURL));
 
     runEventLoop();
 
     // This should be called before we start the shutdown procedure.
     workerReportingProxy().willDestroyWorkerGlobalScope();
 
     ThreadIdentifier threadID = m_threadID;
 
@@ skipping 97 matching lines @@
     }
     m_runLoop.terminate();
 }
 
 bool WorkerThread::isCurrentThread() const
 {
     return m_threadID == currentThread();
 }
 
 } // namespace WebCore