cros: Remove ash reference from ArcKioskAppLauncher

For mustash (out-of-process ash, see //ash/README.md) code in the
browser process cannot call directly into ash.

Pin the kiosk app window by setting a window property instead of
calling into ash code.

Test:
* Add logging to ArcKioskAppLauncher and deploy to Chromebook
* Enterprise enroll Chromebook to test domain
* Move Chromebook to ARC++ test organizational unit
* Sign in and allow policy to force-push app
* Sign out, observe app auto-launch
* Hit escape, see toast saying app is pinned fullscreen
* Observe logs in /var/log/ui/ui.LATEST

Bug: 756056
Change-Id: I8ac35030bf8b44429096a14ec9a6ad71617e85d8
Reviewed-on: https://chromium-review.googlesource.com/1037775Reviewed-by: Sergey Poromov <poromov@chromium.org>
Commit-Queue: James Cook <jamescook@chromium.org>
Cr-Commit-Position: refs/heads/master@{#555397}

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

@@ -7,7 +7,8 @@
 #include <memory>
 #include <string>
 
-#include "ash/wm/window_util.h"
+#include "ash/public/cpp/window_properties.h"
+#include "ash/public/interfaces/window_pin_type.mojom.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"
@@ -78,7 +79,8 @@ bool ArcKioskAppLauncher::CheckAndPinWindow(aura::Window* const window) {
     return false;
   // Stop observing as target window is already found.
   StopObserving();
-  ash::wm::PinWindow(window, true /* trusted */);
+  window->SetProperty(ash::kWindowPinTypeKey,
+                      ash::mojom::WindowPinType::TRUSTED_PINNED);
   if (delegate_)
     delegate_->OnAppWindowLaunched();
   return true;