Sync Blob.close() behavior wrt updated spec.

Source/core/dom/DOMURL.cpp

Index: Source/core/dom/DOMURL.cpp
diff --git a/Source/core/dom/DOMURL.cpp b/Source/core/dom/DOMURL.cpp
index 9aa3764185a39971b79b481a9db0f0bc8492a4aa..feba9b94942173c044ff9ce77be4eed4920b3582 100644
--- a/Source/core/dom/DOMURL.cpp
+++ b/Source/core/dom/DOMURL.cpp
@@ -63,10 +63,14 @@ void DOMURL::setInput(const String& value)
     }
 }
 
-String DOMURL::createObjectURL(ExecutionContext* executionContext, Blob* blob)
+String DOMURL::createObjectURL(ExecutionContext* executionContext, Blob* blob, ExceptionState& exceptionState)
 {
     if (!executionContext || !blob)
         return String();
+    if (blob->hasBeenClosed()) {
+        exceptionState.throwDOMException(InvalidStateError, String(blob->isFile() ? "File" : "Blob") + " has been closed.");
+        return String();
+    }
     return createPublicURL(executionContext, blob, blob->uuid());
 }