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

third_party/WebKit/Source/modules/websockets/DocumentWebSocketChannel.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 542 matching lines @@
   WebSocketFrame::OpCode opcode = m_receivingMessageTypeIsText
                                       ? WebSocketFrame::OpCodeText
                                       : WebSocketFrame::OpCodeBinary;
   WebSocketFrame frame(opcode, m_receivingMessageData.data(),
                        m_receivingMessageData.size(), WebSocketFrame::Final);
   InspectorInstrumentation::didReceiveWebSocketFrame(
       document(), m_identifier, frame.opCode, frame.masked, frame.payload,
       frame.payloadLength);
   if (m_receivingMessageTypeIsText) {
     String message = m_receivingMessageData.isEmpty()
-                         ? emptyString()
+                         ? emptyString
                          : String::fromUTF8(m_receivingMessageData.data(),
                                             m_receivingMessageData.size());
     m_receivingMessageData.clear();
     if (message.isNull()) {
       failAsError("Could not decode a text frame as UTF-8.");
       // failAsError may delete this object.
     } else {
       m_client->didReceiveTextMessage(message);
     }
   } else {
@@ skipping 83 matching lines @@
   WebSocketChannel::trace(visitor);
 }
 
 std::ostream& operator<<(std::ostream& ostream,
                          const DocumentWebSocketChannel* channel) {
   return ostream << "DocumentWebSocketChannel "
                  << static_cast<const void*>(channel);
 }
 
 }  // namespace blink