Make HashTraits<QualifiedName>::emptyValue return a const reference

third_party/WebKit/Source/core/dom/QualifiedName.cpp

Index: third_party/WebKit/Source/core/dom/QualifiedName.cpp
diff --git a/third_party/WebKit/Source/core/dom/QualifiedName.cpp b/third_party/WebKit/Source/core/dom/QualifiedName.cpp
index 1ab21b15e4600c1a03622f314885c65ba83d72a0..469923b484ec3b5cd8428505027eb58396877821 100644
--- a/third_party/WebKit/Source/core/dom/QualifiedName.cpp
+++ b/third_party/WebKit/Source/core/dom/QualifiedName.cpp
@@ -120,10 +120,6 @@ void QualifiedName::initAndReserveCapacityForSize(unsigned size) {
   new ((void*)&nullName) QualifiedName(nullAtom, nullAtom, nullAtom, true);
 }
 
-const QualifiedName& QualifiedName::null() {
-  return nullName;
-}
-
 const AtomicString& QualifiedName::localNameUpper() const {
   if (!m_impl->m_localNameUpper)
     m_impl->m_localNameUpper = m_impl->m_localName.upperASCII();