Combine the WM_CHAR with WM_KEY* for key event flow.

ui/aura/remote_window_tree_host_win.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/aura/remote_window_tree_host_win.h"
 
 #include <windows.h>
 
 #include <algorithm>
 
@@ skipping 130 matching lines @@
 }
 
 bool RemoteWindowTreeHostWin::OnMessageReceived(const IPC::Message& message) {
   bool handled = true;
   IPC_BEGIN_MESSAGE_MAP(RemoteWindowTreeHostWin, message)
     IPC_MESSAGE_HANDLER(MetroViewerHostMsg_MouseMoved, OnMouseMoved)
     IPC_MESSAGE_HANDLER(MetroViewerHostMsg_MouseButton, OnMouseButton)
     IPC_MESSAGE_HANDLER(MetroViewerHostMsg_KeyDown, OnKeyDown)
     IPC_MESSAGE_HANDLER(MetroViewerHostMsg_KeyUp, OnKeyUp)
     IPC_MESSAGE_HANDLER(MetroViewerHostMsg_Character, OnChar)
+    IPC_MESSAGE_HANDLER(MetroViewerHostMsg_CharacterForNextKeyEvent,
+                        OnCharForNextKeyEvent)
     IPC_MESSAGE_HANDLER(MetroViewerHostMsg_WindowActivated,
                         OnWindowActivated)
     IPC_MESSAGE_HANDLER(MetroViewerHostMsg_EdgeGesture, OnEdgeGesture)
     IPC_MESSAGE_HANDLER(MetroViewerHostMsg_TouchDown,
                         OnTouchDown)
     IPC_MESSAGE_HANDLER(MetroViewerHostMsg_TouchUp,
                         OnTouchUp)
     IPC_MESSAGE_HANDLER(MetroViewerHostMsg_TouchMoved,
                         OnTouchMoved)
     IPC_MESSAGE_HANDLER(MetroViewerHostMsg_SetCursorPosAck,
@@ skipping 201 matching lines @@
 }
 
 void RemoteWindowTreeHostWin::OnChar(uint32 key_code,
                                      uint32 repeat_count,
                                      uint32 scan_code,
                                      uint32 flags) {
   DispatchKeyboardMessage(ui::ET_KEY_PRESSED, key_code, repeat_count,
                           scan_code, flags, true);
 }
 
+void RemoteWindowTreeHostWin::OnCharForNextKeyEvent(uint32 key_code,
+                                                    uint32 repeat_count,
+                                                    uint32 scan_code,
+                                                    uint32 flags) {
+  ui::RemoteInputMethodPrivateWin* remote_input_method_private =

[jln (very slow on Chromium), 2015/08/17 21:35:07]

It's unfortunate that none of the IPC parameters are validated on-site (in this
file) before being passes to DispatchKeyboardMessage().

Here it looks like most of them are not even used. Could you check that they are
passed as (for instance) 0 and add a comment that if they need to get used, they
should be validated carefully?

[Shu Chen, 2015/08/18 08:49:41]

Done. I've removed the unused parameters.

+      GetRemoteInputMethodPrivate();
+  if (remote_input_method_private) {
+    remote_input_method_private->OnCharForNextKeyEvent(
+        static_cast<base::char16>(key_code));
+  }
+}
+
 void RemoteWindowTreeHostWin::OnWindowActivated(bool repaint) {
   OnHostActivated();
   if (repaint && compositor())
     compositor()->ScheduleFullRedraw();
 }
 
 void RemoteWindowTreeHostWin::OnEdgeGesture() {
   ui::GestureEvent event(
       0,
       0,
@@ skipping 123 matching lines @@
 }
 
 void RemoteWindowTreeHostWin::SetEventFlags(uint32 flags) {
   if (flags == event_flags_)
     return;
   event_flags_ = flags;
   SetVirtualKeyStates(event_flags_);
 }
 
 }  // namespace aura