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

third_party/WebKit/Source/core/css/FontFace.cpp

 /*
  * Copyright (C) 2013 Google 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 344 matching lines @@
       return "unloaded";
     case Loading:
       return "loading";
     case Loaded:
       return "loaded";
     case Error:
       return "error";
     default:
       NOTREACHED();
   }
-  return emptyString();
+  return emptyString;
 }
 
 void FontFace::setLoadStatus(LoadStatusType status) {
   m_status = status;
   ASSERT(m_status != Error || m_error);
 
   // When promises are resolved with 'thenables', instead of the object being
   // returned directly, the 'then' method is executed (the resolver tries to
   // resolve the thenable). This can lead to synchronous script execution, so we
   // post a task. This does not apply to promise rejection (i.e. a thenable
@@ skipping 296 matching lines @@
 
 bool FontFace::hadBlankText() const {
   return m_cssFontFace->hadBlankText();
 }
 
 bool FontFace::hasPendingActivity() const {
   return m_status == Loading && getExecutionContext();
 }
 
 }  // namespace blink