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

third_party/WebKit/Source/web/tests/KeyboardTest.cpp

 /*
  * Copyright (C) 2010 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 38 matching lines @@
   const char* interpretKeyEvent(const WebKeyboardEvent& webKeyboardEvent) {
     KeyboardEvent* keyboardEvent = KeyboardEvent::create(webKeyboardEvent, 0);
     std::unique_ptr<Settings> settings = Settings::create();
     EditingBehavior behavior(settings->getEditingBehaviorType());
     return behavior.interpretKeyEvent(*keyboardEvent);
   }
 
   WebKeyboardEvent createFakeKeyboardEvent(char keyCode,
                                            int modifiers,
                                            WebInputEvent::Type type,
-                                           const String& key = emptyString()) {
+                                           const String& key = emptyString) {
     WebKeyboardEvent event(type, modifiers, WebInputEvent::TimeStampForTesting);
     event.text[0] = keyCode;
     event.windowsKeyCode = keyCode;
     event.domKey = Platform::current()->domKeyEnumFromString(key);
     return event;
   }
 
   // Like interpretKeyEvent, but with pressing down OSModifier+|keyCode|.
   // OSModifier is the platform's standard modifier key: control on most
   // platforms, but meta (command) on Mac.
@@ skipping 102 matching lines @@
     const char* command;
   } kDomKeyTestCases[] = {
       {"Copy", "Copy"}, {"Cut", "Cut"}, {"Paste", "Paste"},
   };
 
   for (const auto& test_case : kDomKeyTestCases)
     EXPECT_STREQ(test_case.command, interpretDomKey(test_case.key));
 }
 
 }  // namespace blink