Combine the WM_CHAR with WM_KEY* for key event flow.

win8/metro_driver/chrome_app_view_ash.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 "win8/metro_driver/stdafx.h"
 #include "win8/metro_driver/chrome_app_view_ash.h"
 
 #include <corewindow.h>
 #include <shellapi.h>
 #include <windows.foundation.h>
@@ skipping 1249 matching lines @@
   unsigned int char_code = 0;
   HRESULT hr = args->get_KeyCode(&char_code);
   if (FAILED(hr))
     return hr;
 
   winui::Core::CorePhysicalKeyStatus status;
   hr = args->get_KeyStatus(&status);
   if (FAILED(hr))
     return hr;
 
-  ui_channel_->Send(new MetroViewerHostMsg_Character(char_code,
-                                                     status.RepeatCount,
-                                                     status.ScanCode,
-                                                     GetKeyboardEventFlags()));
+  if (status.WasKeyDown) {
+    ui_channel_->Send(new MetroViewerHostMsg_CharacterForNextKeyEvent(
+        char_code, status.RepeatCount, status.ScanCode,

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

Most of these parameters don't seem to be used. Could you force sending them as
0 so that the other side can validate them as being 0?

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

Done.

+        GetKeyboardEventFlags()));
+  } else {
+    ui_channel_->Send(new MetroViewerHostMsg_Character(
+        char_code, status.RepeatCount, status.ScanCode,
+        GetKeyboardEventFlags()));
+  }
   return S_OK;
 }
 
 HRESULT ChromeAppViewAsh::OnWindowActivated(
     winui::Core::ICoreWindow* sender,
     winui::Core::IWindowActivatedEventArgs* args) {
   if (!ui_channel_)
     return S_OK;
 
   if (args) {
@@ skipping 176 matching lines @@
   mswr::ComPtr<winapp::Core::ICoreApplicationExit> app_exit;
   CheckHR(core_app.As(&app_exit));
   globals.app_exit = app_exit.Detach();
 }
 
 IFACEMETHODIMP
 ChromeAppViewFactory::CreateView(winapp::Core::IFrameworkView** view) {
   *view = mswr::Make<ChromeAppViewAsh>().Detach();
   return (*view) ? S_OK :  E_OUTOFMEMORY;
 }