Trigger `window.onerror` only for exceptions thrown in the same world.

Source/core/dom/ScriptExecutionContext.cpp

 /*
  * Copyright (C) 2008 Apple Inc. All Rights Reserved.
  * Copyright (C) 2012 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 223 matching lines @@
 }
 
 bool ScriptExecutionContext::dispatchErrorEvent(PassRefPtr<ErrorEvent> event, AccessControlStatus corsStatus)
 {
     EventTarget* target = errorEventTarget();
     if (!target)
         return false;
 
     RefPtr<ErrorEvent> errorEvent = event;
     if (shouldSanitizeScriptError(errorEvent->filename(), corsStatus))
-        errorEvent = ErrorEvent::createSanitizedError();
+        errorEvent = ErrorEvent::createSanitizedError(errorEvent->world());
 
     ASSERT(!m_inDispatchErrorEvent);
     m_inDispatchErrorEvent = true;
     target->dispatchEvent(errorEvent);
     m_inDispatchErrorEvent = false;
     return errorEvent->defaultPrevented();
 }
 
 int ScriptExecutionContext::circularSequentialID()
 {
@@ skipping 58 matching lines @@
 ScriptExecutionContext::Task::~Task()
 {
 }
 
 void ScriptExecutionContext::setDatabaseContext(DatabaseContext* databaseContext)
 {
     m_databaseContext = databaseContext;
 }
 
 } // namespace WebCore