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

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

 /*
  * (C) 1999 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2012, 2013 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 548 matching lines @@
 
 // StringHash is the default hash for String
 template <typename T>
 struct DefaultHash;
 template <>
 struct DefaultHash<String> {
   typedef StringHash Hash;
 };
 
 // Shared global empty string.
-WTF_EXPORT const String& emptyString();
-WTF_EXPORT const String& emptyString16Bit();
+WTF_EXPORT extern const String& emptyString;
+WTF_EXPORT extern const String& emptyString16Bit;
 WTF_EXPORT extern const String& xmlnsWithColon;
 
 // Pretty printer for gtest and base/logging.*.  It prepends and appends
 // double-quotes, and escapes chracters other than ASCII printables.
 WTF_EXPORT std::ostream& operator<<(std::ostream&, const String&);
 
 inline StringView::StringView(const String& string,
                               unsigned offset,
                               unsigned length)
     : StringView(string.impl(), offset, length) {}
@@ skipping 12 matching lines @@
 using WTF::String;
 using WTF::emptyString;
 using WTF::emptyString16Bit;
 using WTF::charactersAreAllASCII;
 using WTF::equal;
 using WTF::find;
 using WTF::isSpaceOrNewline;
 
 #include "wtf/text/AtomicString.h"
 #endif  // WTFString_h