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

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

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller ( mueller@kde.org )
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2013 Apple Inc. All
  * rights reserved.
  * Copyright (C) 2006 Andrew Wellington (proton@wiretapped.net)
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
@@ skipping 785 matching lines @@
       Unicode::toUpper(data16, length, source16, m_length, &error);
   if (!error && realLength == length)
     return newImpl;
   newImpl = createUninitialized(realLength, data16);
   Unicode::toUpper(data16, realLength, source16, m_length, &error);
   if (error)
     return this;
   return newImpl.release();
 }
 
+PassRefPtr<StringImpl> StringImpl::upperASCII() {
+  if (is8Bit()) {
+    LChar* data8;
+    RefPtr<StringImpl> newImpl = createUninitialized(m_length, data8);
+
+    for (unsigned i = 0; i < m_length; ++i) {
+      LChar c = characters8()[i];
+      data8[i] = isASCIILower(c) ? toASCIIUpper(c) : c;
+    }
+    return newImpl.release();
+  }
+
+  UChar* data16;
+  RefPtr<StringImpl> newImpl = createUninitialized(m_length, data16);
+
+  for (unsigned i = 0; i < m_length; ++i) {
+    UChar c = characters16()[i];
+    data16[i] = isASCIILower(c) ? toASCIIUpper(c) : c;
+  }
+  return newImpl.release();
+}
+
 static inline bool localeIdMatchesLang(const AtomicString& localeId,
                                        const StringView& lang) {
   RELEASE_ASSERT(lang.length() >= 2 && lang.length() <= 3);
   if (!localeId.impl() || !localeId.impl()->startsWithIgnoringCase(lang))
     return false;
   if (localeId.impl()->length() == lang.length())
     return true;
   const UChar maybeDelimiter = (*localeId.impl())[lang.length()];
   return maybeDelimiter == '-' || maybeDelimiter == '_' ||
          maybeDelimiter == '@';
@@ skipping 1397 matching lines @@
     } else if (localeIdMatchesLang(localeIdentifier, "lt")) {
       // TODO(rob.buis) implement upper-casing rules for lt
       // like in StringImpl::upper(locale).
     }
   }
 
   return toUpper(c);
 }
 
 }  // namespace WTF