Make createElement tag name case handling consistent for custom elements

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

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  *           (C) 2006 Alexey Proskuryakov (ap@webkit.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2011, 2012 Apple Inc. All
  * rights reserved.
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved.
  * (http://www.torchmobile.com/)
  * Copyright (C) 2008, 2009, 2011, 2012 Google Inc. All rights reserved.
@@ skipping 624 matching lines @@
 }
 
 bool Document::isInMainFrame() const {
   return frame() && frame()->isMainFrame();
 }
 
 AtomicString Document::convertLocalName(const AtomicString& name) {
   return isHTMLDocument() ? name.lower() : name;
 }
 
+// https://dom.spec.whatwg.org/#dom-document-createelement
 Element* Document::createElement(const AtomicString& name,
                                  ExceptionState& exceptionState) {
   if (!isValidName(name)) {
     exceptionState.throwDOMException(
         InvalidCharacterError,
         "The tag name provided ('" + name + "') is not a valid name.");
     return nullptr;
   }
 
   if (isXHTMLDocument() || isHTMLDocument()) {
-    if (CustomElement::shouldCreateCustomElement(name))
-      return CustomElement::createCustomElementSync(*this, name,
+    // 2. If the context object is an HTML document, let localName be
+    // converted to ASCII lowercase.
+    AtomicString localName = convertLocalName(name);
+    if (CustomElement::shouldCreateCustomElement(localName))
+      return CustomElement::createCustomElementSync(*this, localName,
                                                     exceptionState);
-    return HTMLElementFactory::createHTMLElement(convertLocalName(name), *this,
-                                                 0, CreatedByCreateElement);
+    return HTMLElementFactory::createHTMLElement(localName, *this, 0,
+                                                 CreatedByCreateElement);
   }
 
   return Element::create(QualifiedName(nullAtom, name, nullAtom), this);
 }
 
 Element* Document::createElement(const AtomicString& localName,
                                  const AtomicString& typeExtension,
                                  ExceptionState& exceptionState) {
   if (!isValidName(localName)) {
     exceptionState.throwDOMException(
         InvalidCharacterError,
         "The tag name provided ('" + localName + "') is not a valid name.");
     return nullptr;
   }
 
   Element* element;
 
-  if (CustomElement::shouldCreateCustomElement(localName)) {
-    element = CustomElement::createCustomElementSync(*this, localName,
-                                                     exceptionState);
+  if (CustomElement::shouldCreateCustomElement(convertLocalName(localName))) {
+    element = CustomElement::createCustomElementSync(
+        *this, convertLocalName(localName), exceptionState);
   } else if (V0CustomElement::isValidName(localName) && registrationContext()) {
     element = registrationContext()->createCustomTagElement(
         *this, QualifiedName(nullAtom, convertLocalName(localName),
                              xhtmlNamespaceURI));
   } else {
     element = createElement(localName, exceptionState);
     if (exceptionState.hadException())
       return nullptr;
   }
 
@@ skipping 5701 matching lines @@
 }
 
 void showLiveDocumentInstances() {
   WeakDocumentSet& set = liveDocumentSet();
   fprintf(stderr, "There are %u documents currently alive:\n", set.size());
   for (Document* document : set)
     fprintf(stderr, "- Document %p URL: %s\n", document,
             document->url().getString().utf8().data());
 }
 #endif