Measure the impact of a propsed change to createAttribute()

Source/core/dom/Document.cpp

Index: Source/core/dom/Document.cpp
diff --git a/Source/core/dom/Document.cpp b/Source/core/dom/Document.cpp
index bb1befff42ad782cca0803922720d80baf23c5b1..3864deea2aee5e9947d3edc38408d1937735e4bf 100644
--- a/Source/core/dom/Document.cpp
+++ b/Source/core/dom/Document.cpp
@@ -4480,6 +4480,8 @@ WeakPtrWillBeRawPtr<Document> Document::contextDocument()
 
 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);
 }