linux-aura: Supports Compose key with XIM.

ui/events/x/events_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/event_constants.h"
 
 #include <cmath>
 #include <string.h>
 #include <X11/extensions/XInput.h>
 #include <X11/extensions/XInput2.h>
@@ skipping 131 matching lines @@
   if (state & Button1Mask)
     flags |= ui::EF_LEFT_MOUSE_BUTTON;
   if (state & Button2Mask)
     flags |= ui::EF_MIDDLE_MOUSE_BUTTON;
   if (state & Button3Mask)
     flags |= ui::EF_RIGHT_MOUSE_BUTTON;
   return flags;
 }
 
 int GetEventFlagsFromXKeyEvent(XEvent* xevent) {
+  DCHECK(xevent->type == KeyPress || xevent->type == KeyRelease);
+
+#if defined(OS_CHROMEOS)
+  const int ime_fabricated_flag = 0;
+#else
+  // XIM fabricates key events for the character compositions by XK_Multi_key.
+  // For example, when a user hits XK_Multi_key, XK_apostrophe, and XK_e in
+  // order to input "é", then XIM generates a key event with keycode=0 and
+  // state=0 for the composition, and the sequence of X11 key events will be
+  // XK_Multi_key, XK_apostrophe, **NoSymbol**, and XK_e.
+  //
+  // We have to send these fabricated key events to XIM so it can correctly
+  // handle the character compositions.
+  const bool fabricated_by_xim =
+      xevent->xkey.keycode == 0 && xevent->xkey.state == 0;
+  const int ime_fabricated_flag =
+      fabricated_by_xim ? ui::EF_IME_FABRICATED_KEY : 0;
+#endif
+
   return GetEventFlagsFromXState(xevent->xkey.state) |
-         (IsKeypadKey(XLookupKeysym(&xevent->xkey, 0)) ? ui::EF_NUMPAD_KEY : 0);
+      (IsKeypadKey(XLookupKeysym(&xevent->xkey, 0)) ? ui::EF_NUMPAD_KEY : 0) |
+      ime_fabricated_flag;
 }
 
 // Get the event flag for the button in XButtonEvent. During a ButtonPress
 // event, |state| in XButtonEvent does not include the button that has just been
 // pressed. Instead |state| contains flags for the buttons (if any) that had
 // already been pressed before the current button, and |button| stores the most
 // current pressed button. So, if you press down left mouse button, and while
 // pressing it down, press down the right mouse button, then for the latter
 // event, |state| would have Button1Mask set but not Button3Mask, and |button|
 // would be 3.
@@ skipping 506 matching lines @@
   DeviceDataManager::GetInstance()->GetGestureTimes(
       native_event, start_time, end_time);
   return true;
 }
 
 bool IsTouchpadEvent(const base::NativeEvent& event) {
   return DeviceDataManager::GetInstance()->IsTouchpadXInputEvent(event);
 }
 
 }  // namespace ui