[ozone] Keep the queue of surfaceless buffers inside gl_surface_ozone

ui/ozone/platform/drm/gpu/page_flip_request.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 "ui/ozone/platform/drm/gpu/page_flip_request.h"
+
+#include "base/barrier_closure.h"
+
+namespace ui {
+
+PageFlipRequest::PageFlipRequest(int crtc_count, const base::Closure& callback)
+    : callback_(base::BarrierClosure(crtc_count, callback)) {
+}
+
+PageFlipRequest::~PageFlipRequest() {
+}
+
+void PageFlipRequest::Signal() {
+  callback_.Run();
+}
+
+}  // namespace ui