mash: Migrate wallpaper controllers to ash/common.

chrome/browser/chromeos/login/kiosk_browsertest.cc

Index: chrome/browser/chromeos/login/kiosk_browsertest.cc
diff --git a/chrome/browser/chromeos/login/kiosk_browsertest.cc b/chrome/browser/chromeos/login/kiosk_browsertest.cc
index b05bfa2fcdb5f1d40b15ae3326c6cd4c45820dd1..a18ef09ebebe9504a973a588f8f2465ccbf50049 100644
--- a/chrome/browser/chromeos/login/kiosk_browsertest.cc
+++ b/chrome/browser/chromeos/login/kiosk_browsertest.cc
@@ -5,9 +5,9 @@
 #include <memory>
 #include <vector>
 
-#include "ash/shell.h"
-#include "ash/wallpaper/wallpaper_controller.h"
-#include "ash/wallpaper/wallpaper_controller_observer.h"
+#include "ash/common/wallpaper/wallpaper_controller.h"
+#include "ash/common/wallpaper/wallpaper_controller_observer.h"
+#include "ash/common/wm_shell.h"
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/files/file_util.h"
@@ -78,6 +78,7 @@
 #include "google_apis/gaia/gaia_switches.h"
 #include "google_apis/gaia/gaia_urls.h"
 #include "net/test/embedded_test_server/embedded_test_server.h"
+#include "ui/aura/window.h"
 #include "ui/base/accelerators/accelerator.h"
 
 namespace em = enterprise_management;
@@ -2346,11 +2347,11 @@ class KioskHiddenWebUITest : public KioskTest,
     LoginDisplayHostImpl::DisableRestrictiveProxyCheckForTest();
 
     KioskTest::SetUpOnMainThread();
-    ash::Shell::GetInstance()->wallpaper_controller()->AddObserver(this);
+    ash::WmShell::Get()->wallpaper_controller()->AddObserver(this);
   }
 
   void TearDownOnMainThread() override {
-    ash::Shell::GetInstance()->wallpaper_controller()->RemoveObserver(this);
+    ash::WmShell::Get()->wallpaper_controller()->RemoveObserver(this);
     KioskTest::TearDownOnMainThread();
   }