Use OnceCallback on Mojo interfaces in //ash

ash/wm/session_state_animator_impl.h

Index: ash/wm/session_state_animator_impl.h
diff --git a/ash/wm/session_state_animator_impl.h b/ash/wm/session_state_animator_impl.h
index 8181d757f3be11f77638e2eef6f64706e33b15ed..794bd5f65d5dfb8200b5f0e7e5d13891e6ebc68f 100644
--- a/ash/wm/session_state_animator_impl.h
+++ b/ash/wm/session_state_animator_impl.h
@@ -56,8 +56,9 @@ class ASH_EXPORT SessionStateAnimatorImpl : public SessionStateAnimator {
   void StartAnimationWithCallback(int container_mask,
                                   AnimationType type,
                                   AnimationSpeed speed,
-                                  base::Closure callback) override;
-  AnimationSequence* BeginAnimationSequence(base::Closure callback) override;
+                                  base::OnceClosure callback) override;
+  AnimationSequence* BeginAnimationSequence(
+      base::OnceClosure callback) override;
   bool IsWallpaperHidden() const override;
   void ShowWallpaper() override;
   void HideWallpaper() override;