Measure the impact of a propsed change to createAttribute()

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 4462 matching lines @@
         return this;
 #else
         return m_weakFactory.createWeakPtr();
 #endif
     }
     return WeakPtrWillBeRawPtr<Document>(nullptr);
 }
 
 PassRefPtrWillBeRawPtr<Attr> Document::createAttribute(const AtomicString& name, ExceptionState& exceptionState)
 {
+    if (isHTMLDocument() && name != name.lower())
+        UseCounter::count(*this, UseCounter::HTMLDocumentCreateAttributeNameNotLowercase);
     return createAttributeNS(nullAtom, name, exceptionState, true);
 }
 
 PassRefPtrWillBeRawPtr<Attr> Document::createAttributeNS(const AtomicString& namespaceURI, const AtomicString& qualifiedName, ExceptionState& exceptionState, bool shouldIgnoreNamespaceChecks)
 {
     AtomicString prefix, localName;
     if (!parseQualifiedName(qualifiedName, prefix, localName, exceptionState))
         return nullptr;
 
     QualifiedName qName(prefix, localName, namespaceURI);
@@ skipping 1274 matching lines @@
 #ifndef NDEBUG
 using namespace blink;
 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().string().utf8().data());
 }
 #endif