mash: Migrate wallpaper controllers to ash/common.

chrome/browser/chromeos/login/lock/screen_locker.cc

Index: chrome/browser/chromeos/login/lock/screen_locker.cc
diff --git a/chrome/browser/chromeos/login/lock/screen_locker.cc b/chrome/browser/chromeos/login/lock/screen_locker.cc
index 94f2fba9129df28aa19efebd3844f86d675c6e32..7df31b62eb8d60b9d7af19d07d6e60c7c7caf9bd 100644
--- a/chrome/browser/chromeos/login/lock/screen_locker.cc
+++ b/chrome/browser/chromeos/login/lock/screen_locker.cc
@@ -8,10 +8,11 @@
 #include <vector>
 
 #include "ash/common/ash_switches.h"
+#include "ash/common/wallpaper/wallpaper_controller.h"
 #include "ash/common/wm/window_state.h"
 #include "ash/common/wm/wm_event.h"
+#include "ash/common/wm_shell.h"
 #include "ash/shell.h"
-#include "ash/wallpaper/wallpaper_controller.h"
 #include "ash/wm/lock_state_controller.h"
 #include "ash/wm/window_state_aura.h"
 #include "ash/wm/window_util.h"
@@ -492,7 +493,7 @@ ScreenLocker::~ScreenLocker() {
   ClearErrors();
 
   VLOG(1) << "Moving wallpaper to unlocked container";
-  ash::Shell::GetInstance()->wallpaper_controller()->MoveToUnlockedContainer();
+  ash::WmShell::Get()->wallpaper_controller()->MoveToUnlockedContainer();
 
   screen_locker_ = NULL;
   bool state = false;
@@ -523,7 +524,7 @@ void ScreenLocker::ScreenLockReady() {
   UMA_HISTOGRAM_TIMES("ScreenLocker.ScreenLockTime", delta);
 
   VLOG(1) << "Moving wallpaper to locked container";
-  ash::Shell::GetInstance()->wallpaper_controller()->MoveToLockedContainer();
+  ash::WmShell::Get()->wallpaper_controller()->MoveToLockedContainer();
 
   bool state = true;
   VLOG(1) << "Emitting SCREEN_LOCK_STATE_CHANGED with state=" << state;