Replace WTF::emptyString{16Bit}() with a static global

third_party/WebKit/Source/core/html/parser/TextResourceDecoder.cpp

 /*
     Copyright (C) 1999 Lars Knoll (knoll@mpi-hd.mpg.de)
     Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2012 Apple Inc. All
     rights reserved.
     Copyright (C) 2005, 2006, 2007 Alexey Proskuryakov (ap@nypop.com)
 
     This library is free software; you can redistribute it and/or
     modify it under the terms of the GNU Library General Public
     License as published by the Free Software Foundation; either
     version 2 of the License, or (at your option) any later version.
@@ skipping 416 matching lines @@
 
 String TextResourceDecoder::decode(const char* data, size_t len) {
   size_t lengthOfBOM = 0;
   if (!m_checkedForBOM) {
     lengthOfBOM = checkForBOM(data, len);
 
     // BOM check can fail when the available data is not enough.
     if (!m_checkedForBOM) {
       DCHECK_EQ(0u, lengthOfBOM);
       m_buffer.append(data, len);
-      return emptyString();
+      return emptyString;
     }
   }
   DCHECK_LE(lengthOfBOM, m_buffer.size() + len);
 
   bool movedDataToBuffer = false;
 
   if (m_contentType == CSSContent && !m_checkedForCSSCharset) {
     if (!checkForCSSCharset(data, len, movedDataToBuffer))
-      return emptyString();
+      return emptyString;
   }
 
   // We check XML declaration in HTML content only if there is enough data
   // available
   if (((m_contentType == HTMLContent && len >= minimumLengthOfXMLDeclaration) ||
        m_contentType == XMLContent) &&
       !m_checkedForXMLCharset) {
     if (!checkForXMLCharset(data, len, movedDataToBuffer))
-      return emptyString();
+      return emptyString;
   }
 
   const char* dataForDecode = data + lengthOfBOM;
   size_t lengthForDecode = len - lengthOfBOM;
 
   if (!m_buffer.isEmpty()) {
     if (!movedDataToBuffer) {
       size_t oldSize = m_buffer.size();
       m_buffer.grow(oldSize + len);
       memcpy(m_buffer.data() + oldSize, data, len);
@@ skipping 46 matching lines @@
   String result = m_codec->decode(
       m_buffer.data(), m_buffer.size(), FetchEOF,
       m_contentType == XMLContent && !m_useLenientXMLDecoding, m_sawError);
   m_buffer.clear();
   m_codec.reset();
   m_checkedForBOM = false;  // Skip BOM again when re-decoding.
   return result;
 }
 
 }  // namespace blink