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

third_party/WebKit/Source/core/xml/XSLStyleSheet.h

 /*
  * This file is part of the XSL implementation.
  *
  * Copyright (C) 2004, 2006, 2008, 2012 Apple Inc. All rights reserved.
  *
  * 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 80 matching lines @@
   void clearDocuments();
 
   void markAsProcessed();
   bool processed() const { return m_processed; }
 
   String type() const override { return "text/xml"; }
   bool disabled() const override { return m_isDisabled; }
   void setDisabled(bool b) override { m_isDisabled = b; }
   Node* ownerNode() const override { return m_ownerNode; }
   String href() const override { return m_originalURL; }
-  String title() const override { return emptyString(); }
+  String title() const override { return emptyString; }
 
   void clearOwnerNode() override { m_ownerNode = nullptr; }
   KURL baseURL() const override { return m_finalURL; }
   bool isLoading() const override;
 
   DECLARE_VIRTUAL_TRACE();
 
  private:
   XSLStyleSheet(Node* parentNode,
                 const String& originalURL,
@@ skipping 28 matching lines @@
 
 DEFINE_TYPE_CASTS(XSLStyleSheet,
                   StyleSheet,
                   sheet,
                   !sheet->isCSSStyleSheet(),
                   !sheet.isCSSStyleSheet());
 
 }  // namespace blink
 
 #endif  // XSLStyleSheet_h