Remove superfluous isNull checks

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.
  * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies)
  * Copyright (C) Research In Motion Limited 2010-2011. All rights reserved.
@@ skipping 715 matching lines @@
     RefPtr<Element> element;
 
     if (RuntimeEnabledFeatures::customElementsEnabled() && CustomElement::isValidName(localName) && registrationContext()) {
         element = registrationContext()->createCustomTagElement(*this, QualifiedName(nullAtom, localName, xhtmlNamespaceURI));
     } else {
         element = createElement(localName, exceptionState);
         if (exceptionState.hadException())
             return 0;
     }
 
-    if (RuntimeEnabledFeatures::customElementsEnabled() && !typeExtension.isNull() && !typeExtension.isEmpty())
+    if (RuntimeEnabledFeatures::customElementsEnabled() && !typeExtension.isEmpty())
         CustomElementRegistrationContext::setIsAttributeAndTypeExtension(element.get(), typeExtension);
 
     return element;
 }
 
 PassRefPtr<Element> Document::createElementNS(const AtomicString& namespaceURI, const AtomicString& qualifiedName, const AtomicString& typeExtension, ExceptionState& exceptionState)
 {
     AtomicString prefix, localName;
     if (!parseQualifiedName(qualifiedName, prefix, localName, exceptionState))
         return 0;
 
     QualifiedName qName(prefix, localName, namespaceURI);
     if (!hasValidNamespaceForElements(qName)) {
         exceptionState.throwDOMException(NamespaceError, "The namespace URI provided ('" + namespaceURI + "') is not valid for the qualified name provided ('" + qualifiedName + "').");
         return 0;
     }
 
     RefPtr<Element> element;
     if (CustomElement::isValidName(qName.localName()) && registrationContext()) {
         element = registrationContext()->createCustomTagElement(*this, qName);
     } else {
         element = createElementNS(namespaceURI, qualifiedName, exceptionState);
         if (exceptionState.hadException())
             return 0;
     }
 
-    if (!typeExtension.isNull() && !typeExtension.isEmpty())
+    if (!typeExtension.isEmpty())

[dominicc (has gone to gerrit), 2014/01/30 03:14:40]

What about CustomElementConstructorBuilder.cpp/constructCustomElement?

         CustomElementRegistrationContext::setIsAttributeAndTypeExtension(element.get(), typeExtension);
 
     return element;
 }
 
 ScriptValue Document::registerElement(WebCore::ScriptState* state, const AtomicString& name, ExceptionState& exceptionState)
 {
     return registerElement(state, name, Dictionary(), exceptionState);
 }
 
@@ skipping 4545 matching lines @@
     if (!page->focusController().isActive() || !page->focusController().isFocused())
         return false;
     if (Frame* focusedFrame = page->focusController().focusedFrame()) {
         if (focusedFrame->tree().isDescendantOf(frame()))
             return true;
     }
     return false;
 }
 
 } // namespace WebCore