Merge 67734 - createBlobURL with no argument causes crash....

WebCore/dom/ScriptExecutionContext.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 259 matching lines @@
 }
 
 DOMTimer* ScriptExecutionContext::findTimeout(int timeoutId)
 {
     return m_timeouts.get(timeoutId);
 }
 
 #if ENABLE(BLOB)
 KURL ScriptExecutionContext::createPublicBlobURL(Blob* blob)
 {
+    if (!blob)
+        return KURL();
     KURL publicURL = BlobURL::createURL(this);
     ThreadableBlobRegistry::registerBlobURL(this, publicURL, blob->url());
     m_publicBlobURLs.add(publicURL.string());
     return publicURL;
 }
 
 void ScriptExecutionContext::revokePublicBlobURL(const KURL& url)
 {
     if (m_publicBlobURLs.contains(url.string())) {
         ThreadableBlobRegistry::unregisterBlobURL(this, url);
@@ skipping 28 matching lines @@
     if (isWorkerContext())
         return static_cast<WorkerContext*>(this)->script()->globalData();
 #endif
 
     ASSERT_NOT_REACHED();
     return 0;
 }
 #endif
 
 } // namespace WebCore