Merge 171971 "Add back three deprecated DOM APIs removed from Ch..."

Source/core/dom/Document.cpp

Index: Source/core/dom/Document.cpp
===================================================================
--- Source/core/dom/Document.cpp	(revision 172146)
+++ Source/core/dom/Document.cpp	(working copy)
@@ -4328,12 +4328,22 @@
 
 PassRefPtr<Attr> Document::createAttribute(const AtomicString& name, ExceptionState& exceptionState)
 {
+    return createAttributeNS(nullAtom, name, exceptionState, true);
+}
+
+PassRefPtr<Attr> Document::createAttributeNS(const AtomicString& namespaceURI, const AtomicString& qualifiedName, ExceptionState& exceptionState, bool shouldIgnoreNamespaceChecks)
+{
     AtomicString prefix, localName;
-    if (!parseQualifiedName(name, prefix, localName, exceptionState))
+    if (!parseQualifiedName(qualifiedName, prefix, localName, exceptionState))
         return nullptr;
 
-    QualifiedName qName(prefix, localName, nullAtom);
+    QualifiedName qName(prefix, localName, namespaceURI);
 
+    if (!shouldIgnoreNamespaceChecks && !hasValidNamespaceForAttributes(qName)) {
+        exceptionState.throwDOMException(NamespaceError, "The namespace URI provided ('" + namespaceURI + "') is not valid for the qualified name provided ('" + qualifiedName + "').");
+        return nullptr;
+    }
+
     return Attr::create(*this, qName, emptyAtom);
 }