mash: Migrate SessionStateDelegate interface to wm common types

ash/shell/shell_delegate_impl.cc

Index: ash/shell/shell_delegate_impl.cc
diff --git a/ash/shell/shell_delegate_impl.cc b/ash/shell/shell_delegate_impl.cc
index 6bf433f6c984788deaec3ccaca1ad66362334a52..e35da8627957677bab391932d1f2ac8a40f5d020 100644
--- a/ash/shell/shell_delegate_impl.cc
+++ b/ash/shell/shell_delegate_impl.cc
@@ -116,10 +116,10 @@ class SessionStateDelegateImpl : public SessionStateDelegate {
   const user_manager::UserInfo* GetUserInfo(UserIndex index) const override {
     return user_info_.get();
   }
-  bool ShouldShowAvatar(aura::Window* window) const override {
+  bool ShouldShowAvatar(WmWindow* window) const override {
     return !user_info_->GetImage().isNull();
   }
-  gfx::ImageSkia GetAvatarImageForWindow(aura::Window* window) const override {
+  gfx::ImageSkia GetAvatarImageForWindow(WmWindow* window) const override {
     return gfx::ImageSkia();
   }
   void SwitchActiveUser(const AccountId& account_id) override {}