Revise ui::DomKey to unify character and non-character codes.

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 882 matching lines @@
     InitXKeyEventFromXIDeviceEvent(*xev, &xkeyevent);
     xkey = &xkeyevent.xkey;
   } else {
     xkey = &xev->xkey;
   }
   KeySym keysym = XK_VoidSymbol;
   XLookupString(const_cast<XKeyEvent*>(xkey), NULL, 0, &keysym, NULL);
   return GetUnicodeCharacterFromXKeySym(keysym);
 }
 
-void GetMeaningFromXEvent(const XEvent* xev, DomKey* key, base::char16* ch) {
+DomKey GetDomKeyFromXEvent(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;
   } else {
     xkey = &xev->xkey;
   }
   KeySym keysym = XK_VoidSymbol;
   XLookupString(const_cast<XKeyEvent*>(xkey), NULL, 0, &keysym, NULL);
-  *ch = GetUnicodeCharacterFromXKeySym(keysym);
-  *key = XKeySymToDomKey(keysym, *ch);
+  base::char16 ch = GetUnicodeCharacterFromXKeySym(keysym);
+  return XKeySymToDomKey(keysym, ch);
 }
 
 KeyboardCode DefaultKeyboardCodeFromHardwareKeycode(
     unsigned int hardware_code) {
   // This function assumes that X11 is using evdev-based keycodes.
   static const KeyboardCode kHardwareKeycodeMap[] = {
       // Please refer to below links for the table content:
       // http://www.w3.org/TR/DOM-Level-3-Events-code/#keyboard-101
       // https://developer.mozilla.org/en-US/docs/Web/API/KeyboardEvent.keyCode
       // http://download.microsoft.com/download/1/6/1/161ba512-40e2-4cc9-843a-923143f3456c/translate.pdf
@@ skipping 474 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