Put OOBE UI on touch display if no keyboard detected

chrome/browser/chromeos/login/ui/login_display_host_impl.cc

 // Copyright 2014 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 "chrome/browser/chromeos/login/ui/login_display_host_impl.h"
 
 #include <utility>
 #include <vector>
 
 #include "ash/public/cpp/shell_window_ids.h"
@@ skipping 957 matching lines @@
 // LoginDisplayHostImpl, chromeos::CrasAudioHandler::AudioObserver:
 
 void LoginDisplayHostImpl::OnActiveOutputNodeChanged() {
   TryToPlayStartupSound();
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 // LoginDisplayHostImpl, display::DisplayObserver:
 
 void LoginDisplayHostImpl::OnDisplayAdded(const display::Display& new_display) {
+  if (GetOobeUI())
+    GetOobeUI()->OnDisplayAdded();
 }

[oshima, 2017/05/10 00:14:31]

I think you need to handle removed case. 

- You have one non touch + two touch displays
- Removing a touch display that is used as a primary will change
 the display configuration. It may or may not use the touch capable one.

[Felix Ekblom, 2017/05/10 10:59:13]

Addressed in Patch set 3 by triggering a re-evaluation of the display usage on
display removal as well.

 
 void LoginDisplayHostImpl::OnDisplayRemoved(
     const display::Display& old_display) {}
 
 void LoginDisplayHostImpl::OnDisplayMetricsChanged(
     const display::Display& display,
     uint32_t changed_metrics) {
   display::Display primary_display =
       display::Screen::GetScreen()->GetPrimaryDisplay();
   if (display.id() != primary_display.id() ||
@@ skipping 400 matching lines @@
   // Chrome locale. Otherwise it will be lost if Chrome restarts.
   // Don't need to schedule pref save because setting initial local
   // will enforce preference saving.
   prefs->SetString(prefs::kApplicationLocale, locale);
   StartupUtils::SetInitialLocale(locale);
 
   TriggerShowLoginWizardFinish(locale, std::move(data));
 }
 
 }  // namespace chromeos