Mus+Ash: propagate Surface ID to parents

services/ui/ws/test_server_window_delegate.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "services/ui/surfaces/display_compositor.h"
 #include "services/ui/ws/server_window.h"
 #include "services/ui/ws/test_server_window_delegate.h"
 
 namespace ui {
 
 namespace ws {
 
 TestServerWindowDelegate::TestServerWindowDelegate()
-    : root_window_(nullptr), display_compositor_(new DisplayCompositor()) {}
+    : root_window_(nullptr),
+      display_compositor_(new DisplayCompositor(nullptr)) {}
 
 TestServerWindowDelegate::~TestServerWindowDelegate() {}
 
 ui::DisplayCompositor* TestServerWindowDelegate::GetDisplayCompositor() {
   return display_compositor_.get();
 }
 
 void TestServerWindowDelegate::OnScheduleWindowPaint(ServerWindow* window) {}
 
 const ServerWindow* TestServerWindowDelegate::GetRootWindow(
     const ServerWindow* window) const {
   return root_window_;
 }
 
 }  // namespace ws
 
 }  // namespace ui