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

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

 /*
  * Copyright (C) 2010 Apple Inc. All Rights Reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 28 matching lines @@
 WTF_EXPORT DEFINE_GLOBAL(AtomicString, xmlnsAtom);
 WTF_EXPORT DEFINE_GLOBAL(AtomicString, xlinkAtom);
 WTF_EXPORT DEFINE_GLOBAL(AtomicString, httpAtom);
 WTF_EXPORT DEFINE_GLOBAL(AtomicString, httpsAtom);
 
 // This is not an AtomicString because it is unlikely to be used as an
 // event/element/attribute name, so it shouldn't pollute the AtomicString hash
 // table.
 WTF_EXPORT DEFINE_GLOBAL(String, xmlnsWithColon);
 
+WTF_EXPORT DEFINE_GLOBAL(String, emptyString);
+WTF_EXPORT DEFINE_GLOBAL(String, emptyString16Bit);
+
 NEVER_INLINE unsigned StringImpl::hashSlowCase() const {
   if (is8Bit())
     setHash(StringHasher::computeHashAndMaskTop8Bits(characters8(), m_length));
   else
     setHash(StringHasher::computeHashAndMaskTop8Bits(characters16(), m_length));
   return existingHash();
 }
 
 void AtomicString::init() {
   DCHECK(isMainThread());
 
   new (NotNull, (void*)&nullAtom) AtomicString;
   new (NotNull, (void*)&emptyAtom) AtomicString("");
 }
 
 template <unsigned charactersCount>
 PassRefPtr<StringImpl> addStaticASCIILiteral(
     const char (&characters)[charactersCount]) {
   unsigned length = charactersCount - 1;
   unsigned hash = StringHasher::computeHashAndMaskTop8Bits(
       reinterpret_cast<const LChar*>(characters), length);
   return adoptRef(StringImpl::createStatic(characters, length, hash));
 }
 
 void StringStatics::init() {
   DCHECK(isMainThread());
 
   StringImpl::initStatics();
+  new (NotNull, (void*)&emptyString) String(StringImpl::empty);
+  new (NotNull, (void*)&emptyString16Bit) String(StringImpl::empty16Bit);
 
   // FIXME: These should be allocated at compile time.
   new (NotNull, (void*)&starAtom) AtomicString("*");
   new (NotNull, (void*)&xmlAtom) AtomicString(addStaticASCIILiteral("xml"));
   new (NotNull, (void*)&xmlnsAtom) AtomicString(addStaticASCIILiteral("xmlns"));
   new (NotNull, (void*)&xlinkAtom) AtomicString(addStaticASCIILiteral("xlink"));
   new (NotNull, (void*)&xmlnsWithColon) String("xmlns:");
   new (NotNull, (void*)&httpAtom) AtomicString(addStaticASCIILiteral("http"));
   new (NotNull, (void*)&httpsAtom) AtomicString(addStaticASCIILiteral("https"));
 }
 
 }  // namespace WTF