arc: Add splash screen for ARC++ Kiosk startup

chrome/browser/chromeos/app_mode/arc/arc_kiosk_app_launcher.cc

 // Copyright 2016 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/app_mode/arc/arc_kiosk_app_launcher.h>
 
 #include <memory>
 #include <string>
 
 #include "ash/wm/window_util.h"
 #include "chrome/browser/ui/app_list/arc/arc_app_utils.h"
 #include "chrome/browser/ui/ash/launcher/arc_app_window_launcher_controller.h"
 #include "ui/aura/env.h"
 #include "ui/events/event_constants.h"
 
 namespace chromeos {
 
 ArcKioskAppLauncher::ArcKioskAppLauncher(content::BrowserContext* context,
                                          ArcAppListPrefs* prefs,
-                                         const std::string& app_id)
-    : app_id_(app_id), prefs_(prefs) {
+                                         const std::string& app_id,
+                                         Delegate* delegate)
+    : app_id_(app_id), prefs_(prefs), delegate_(delegate) {
   prefs_->AddObserver(this);
   aura::Env::GetInstance()->AddObserver(this);
   // Launching the app by app id in landscape mode and in non-touch mode.
   arc::LaunchApp(context, app_id_, ui::EF_NONE);
 }
 
 ArcKioskAppLauncher::~ArcKioskAppLauncher() {
   StopObserving();
 }
 
@@ skipping 39 matching lines @@
   windows_.erase(window);
 }
 
 bool ArcKioskAppLauncher::CheckAndPinWindow(aura::Window* const window) {
   DCHECK_GE(task_id_, 0);
   if (ArcAppWindowLauncherController::GetWindowTaskId(window) != task_id_)
     return false;
   // Stop observing as target window is already found.
   StopObserving();
   ash::wm::PinWindow(window, true /* trusted */);
+  if (delegate_)
+    delegate_->OnAppWindowLaunched();
   return true;
 }
 
 void ArcKioskAppLauncher::StopObserving() {
   aura::Env::GetInstance()->RemoveObserver(this);
   for (auto* window : windows_)
     window->RemoveObserver(this);
   windows_.clear();
   prefs_->RemoveObserver(this);
 }
 
 }  // namespace chromeos