Use the correct case converter for |localName| and |tagName|

third_party/WebKit/Source/wtf/text/WTFString.cpp

Index: third_party/WebKit/Source/wtf/text/WTFString.cpp
diff --git a/third_party/WebKit/Source/wtf/text/WTFString.cpp b/third_party/WebKit/Source/wtf/text/WTFString.cpp
index b547cbdf993b0a448a1d25a79df6adb28d5a21fa..f59f40b79720200d0f74f6f4bf6437a20bb2e3a8 100644
--- a/third_party/WebKit/Source/wtf/text/WTFString.cpp
+++ b/third_party/WebKit/Source/wtf/text/WTFString.cpp
@@ -294,6 +294,12 @@ String String::upper(const AtomicString& localeIdentifier) const {
   return m_impl->upper(localeIdentifier);
 }
 
+String String::upperASCII() const {
+  if (!m_impl)
+    return String();
+  return m_impl->upperASCII();
+}
+
 String String::stripWhiteSpace() const {
   if (!m_impl)
     return String();