Clean up WebVR RequestPresent and make callback asynchronous.

device/vr/vr_display_impl.h

 // 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.
 
 #ifndef DEVICE_VR_VR_DISPLAY_IMPL_H
 #define DEVICE_VR_VR_DISPLAY_IMPL_H
 
 #include <memory>
 
 #include "base/macros.h"
-
+#include "base/memory/weak_ptr.h"
 #include "device/vr/vr_device.h"
 #include "device/vr/vr_export.h"
 #include "device/vr/vr_service.mojom.h"
 #include "mojo/public/cpp/bindings/binding.h"
 
 namespace device {
 
 class VRDisplayImpl : public mojom::VRDisplay {
  public:
   VRDisplayImpl(device::VRDevice* device, VRServiceImpl* service);
   ~VRDisplayImpl() override;
 
   mojom::VRDisplayClient* client() { return client_.get(); }
 
  private:
   friend class VRServiceImpl;
 
   void GetPose(const GetPoseCallback& callback) override;
   void ResetPose() override;
 
-  void RequestPresent(bool secureOrigin,
+  void RequestPresent(bool secure_origin,
                       const RequestPresentCallback& callback) override;
   void ExitPresent() override;
   void SubmitFrame(mojom::VRPosePtr pose) override;
 
   void UpdateLayerBounds(mojom::VRLayerBoundsPtr left_bounds,
                          mojom::VRLayerBoundsPtr right_bounds) override;
 
+  void RequestPresentResult(const RequestPresentCallback& callback,
+                            bool secure_origin,
+                            bool success);
+
   mojo::Binding<mojom::VRDisplay> binding_;
   mojom::VRDisplayClientPtr client_;
   device::VRDevice* device_;
   VRServiceImpl* service_;
+
+  base::WeakPtrFactory<VRDisplayImpl> weak_ptr_factory_;
 };
 
 }  // namespace device
 
 #endif  //  DEVICE_VR_VR_DISPLAY_IMPL_H