linux/cros: Supports XKeyEvent to Unicode conversion independent from user's locale.

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>
 #include <X11/Xlib.h>
 #include <X11/Xutil.h>
 #include <X11/extensions/XInput2.h>
 #include <X11/keysym.h>
 
 #include "base/basictypes.h"
 #include "base/logging.h"
 #include "base/strings/stringprintf.h"
 #include "base/strings/sys_string_conversions.h"
 #include "base/strings/utf_string_conversions.h"
 #include "ui/events/keycodes/dom4/keycode_converter.h"
+#include "ui/events/x/keysym_to_unicode.h"
 
 #define VKEY_UNSUPPORTED VKEY_UNKNOWN
 
 namespace ui {
 
 namespace {
 
 // MAP0 - MAP3:
 // These are the generated VKEY code maps for all possible Latin keyboard
 // layouts in Windows. And the maps are only for special letter keys excluding
@@ skipping 803 matching lines @@
 
 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);
 }
 
 uint16 GetCharacterFromXEvent(const XEvent* xev) {
   XEvent xkeyevent;
-  const XKeyEvent* xkey = NULL;
-  char buf[6];
+  const XKeyEvent* xkey;

[Wez, 2014/08/08 22:56:25]

nit: Style guide requires local variables be initialized at declaration;
consider initializing to &xev->xkey and then overriding that in the GenericEvent
case? Or might xkey not be initialized in that case?

[Yuki, 2014/08/11 05:58:52]

Done.

   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;
   }
-  int bytes_written =
-      XLookupString(const_cast<XKeyEvent*>(xkey), buf, 6, NULL, NULL);
-  DCHECK_LE(bytes_written, 6);
-
-  if (bytes_written <= 0)
-    return 0;
-  const base::string16& result = base::WideToUTF16(
-      base::SysNativeMBToWide(base::StringPiece(buf, bytes_written)));
-  return result.length() == 1 ? result[0] : 0;
+  KeySym keysym = XK_VoidSymbol;
+  XLookupString(const_cast<XKeyEvent*>(xkey), NULL, 0, &keysym, NULL);
+  return GetUnicodeCharacterFromXKeySym(keysym);
 }
 
 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