Move CreateFakeXEvent to x11_util.{h,cc}.

ui/base/keycodes/keyboard_code_conversion_x.h

 // Copyright (c) 2011 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.
 
 #ifndef UI_BASE_KEYCODES_KEYBOARD_CODE_CONVERSION_X_H_
 #define UI_BASE_KEYCODES_KEYBOARD_CODE_CONVERSION_X_H_
 
+#include "ui/base/events.h"
 #include "ui/base/keycodes/keyboard_codes_posix.h"
 #include "ui/base/ui_export.h"
 
 typedef union _XEvent XEvent;
 
 namespace ui {
 
 UI_EXPORT KeyboardCode KeyboardCodeFromXKeyEvent(XEvent* xev);
 
 UI_EXPORT KeyboardCode KeyboardCodeFromXKeysym(unsigned int keysym);
 
 // Returns a key symbol on a standard US PC keyboard from an XEvent.
 UI_EXPORT unsigned int DefaultSymbolFromXEvent(XEvent* xev);
 
 // Converts a KeyboardCode into an X KeySym.
 UI_EXPORT int XKeysymForWindowsKeyCode(KeyboardCode keycode, bool shift);
 
 // Converts an X keycode into an X KeySym.
 unsigned int DefaultXKeysymFromHardwareKeycode(unsigned int keycode);
 
+// Creates a fake XEvent for testing. The caller must delete the returned value.
+XEvent* CreateXEventForTesting(EventType type,
+                               KeyboardCode key_code,
+                               int flags);
+
 }  // namespace ui
 
 #endif  // UI_BASE_KEYCODES_KEYBOARD_CODE_CONVERSION_X_H_