events: keycodes: Remove the stateless singleton instance of KeycodeConverter

ui/events/keycodes/keyboard_code_conversion_x.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ui/events/keycodes/keyboard_code_conversion_x.h"
 
 #include <algorithm>
 
 #define XK_3270  // for XK_3270_BackTab
 #include <X11/XF86keysym.h>
@@ skipping 820 matching lines @@
     // TODO(sad): some keycodes are still missing.
   }
   DLOG(WARNING) << "Unknown keysym: " << base::StringPrintf("0x%x", keysym);
   return VKEY_UNKNOWN;
 }
 
 const char* CodeFromXEvent(const XEvent* xev) {
   int keycode = (xev->type == GenericEvent)
                     ? static_cast<XIDeviceEvent*>(xev->xcookie.data)->detail
                     : xev->xkey.keycode;
-  return KeycodeConverter::GetInstance()->NativeKeycodeToCode(keycode);
+  return ui::KeycodeConverter::NativeKeycodeToCode(keycode);
 }
 
 uint16 GetCharacterFromXEvent(const XEvent* xev) {
   XEvent xkeyevent = {0};
   const XKeyEvent* xkey = NULL;
   if (xev->type == GenericEvent) {
     // Convert the XI2 key event into a core key event so that we can
     // continue to use XLookupString() until crbug.com/367732 is complete.
     InitXKeyEventFromXIDeviceEvent(*xev, &xkeyevent);
     xkey = &xkeyevent.xkey;
@@ skipping 490 matching lines @@
   // alone does not map to XK_less; XKeysymToKeycode() returns KEY_102ND
   // (the '<>' key between Shift and Z on 105-key keyboards) which does.
   //
   // crbug.com/386066 and crbug.com/390263 are examples of problems
   // associated with this.
   //
   return XKeysymToKeycode(display, XKeysymForWindowsKeyCode(key_code, false));
 }
 
 }  // namespace ui