Remove some dead code in dom/

Source/core/dom/DOMImplementation.cpp

Index: Source/core/dom/DOMImplementation.cpp
diff --git a/Source/core/dom/DOMImplementation.cpp b/Source/core/dom/DOMImplementation.cpp
index ee86054e617c8540c661a10a5bb89f01d2859769..cbfcb17fe556260233a6d2cae2fbe13d4932b422 100644
--- a/Source/core/dom/DOMImplementation.cpp
+++ b/Source/core/dom/DOMImplementation.cpp
@@ -198,11 +198,6 @@ PassRefPtr<DocumentType> DOMImplementation::createDocumentType(const AtomicStrin
     return DocumentType::create(&m_document, qualifiedName, publicId, systemId);
 }
 
-DOMImplementation* DOMImplementation::getInterface(const String& /*feature*/)
-{
-    return 0;
-}
-
 PassRefPtr<XMLDocument> DOMImplementation::createDocument(const AtomicString& namespaceURI,
     const AtomicString& qualifiedName, DocumentType* doctype, ExceptionState& exceptionState)
 {