Use toDocument instead of static_cast<Document*>.

Source/WebKit/chromium/src/SharedWorkerRepository.cpp

 /*
  * 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 209 matching lines @@
 void SharedWorkerRepository::connect(PassRefPtr<SharedWorker> worker, PassOwnPtr<MessagePortChannel> port, const KURL& url, const String& name, ExceptionCode& ec)
 {
     WebKit::WebSharedWorkerRepository* repository = WebKit::sharedWorkerRepository();
 
     // This should not be callable unless there's a SharedWorkerRepository for
     // this context (since isAvailable() should have returned null).
     ASSERT(repository);
 
     // No nested workers (for now) - connect() should only be called from document context.
     ASSERT(worker->scriptExecutionContext()->isDocument());
-    Document* document = static_cast<Document*>(worker->scriptExecutionContext());
+    Document* document = toDocument(worker->scriptExecutionContext());
     WebFrameImpl* webFrame = WebFrameImpl::fromFrame(document->frame());
     OwnPtr<WebSharedWorker> webWorker;
     webWorker = adoptPtr(webFrame->client()->createSharedWorker(webFrame, url, name, getId(document)));
 
     if (!webWorker) {
         // Existing worker does not match this url, so return an error back to the caller.
         ec = URL_MISMATCH_ERR;
         return;
     }
 
@@ skipping 18 matching lines @@
 }
 
 bool SharedWorkerRepository::hasSharedWorkers(Document* document)
 {
     WebKit::WebSharedWorkerRepository* repository = WebKit::sharedWorkerRepository();
 
     return repository && repository->hasSharedWorkers(getId(document));
 }
 
 } // namespace WebCore