Unify mustash display closing code paths.

services/ui/display/platform_screen_stub.cc

 // Copyright 2016 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/display/platform_screen_stub.h"
 
 #include <memory>
 
 #include "base/bind.h"
 #include "base/location.h"
@@ skipping 25 matching lines @@
 void PlatformScreenStub::AddInterfaces(shell::InterfaceRegistry* registry) {}
 
 void PlatformScreenStub::Init(PlatformScreenDelegate* delegate) {
   DCHECK(delegate);
   delegate_ = delegate;
   base::ThreadTaskRunnerHandle::Get()->PostTask(
       FROM_HERE, base::Bind(&PlatformScreenStub::FixedSizeScreenConfiguration,
                             weak_ptr_factory_.GetWeakPtr()));
 }
 
+void PlatformScreenStub::RequestCloseDisplay(int64_t display_id) {
+  if (display_id == kDisplayId) {
+    base::ThreadTaskRunnerHandle::Get()->PostTask(
+        FROM_HERE, base::Bind(&PlatformScreenDelegate::OnDisplayRemoved,
+                              base::Unretained(delegate_), display_id));
+  }
+}
+
 int64_t PlatformScreenStub::GetPrimaryDisplayId() const {
   return kDisplayId;
 }
 
 }  // namespace display