Implement WebVR presentation pausing for VR Shell Menu Mode

device/vr/android/gvr/gvr_device.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_ANDROID_GVR_DEVICE_H
 #define DEVICE_VR_ANDROID_GVR_DEVICE_H
 
 #include "base/macros.h"
+#include "base/memory/weak_ptr.h"
 #include "device/vr/vr_device.h"
 
 namespace gvr {
 class GvrApi;
 }  // namespace gvr
 
 namespace device {
 
 class GvrDeviceProvider;
 class GvrDelegate;
 
 class GvrDevice : public VRDevice {
  public:
-  GvrDevice(GvrDeviceProvider* provider, GvrDelegate* delegate);
+  GvrDevice(GvrDeviceProvider* provider,
+            const base::WeakPtr<GvrDelegate>& delegate);
   ~GvrDevice() override;
 
   // VRDevice
   mojom::VRDisplayInfoPtr GetVRDevice() override;
   mojom::VRPosePtr GetPose(VRServiceImpl* service) override;
   void ResetPose(VRServiceImpl* service) override;
 
   bool RequestPresent(VRServiceImpl* service, bool secure_origin) override;
   void ExitPresent(VRServiceImpl* service) override;
 
   void SubmitFrame(VRServiceImpl* service, mojom::VRPosePtr pose) override;
   void UpdateLayerBounds(VRServiceImpl* service,
                          mojom::VRLayerBoundsPtr leftBounds,
                          mojom::VRLayerBoundsPtr rightBounds) override;
 
-  void SetDelegate(GvrDelegate* delegate);
+  void SetDelegate(const base::WeakPtr<GvrDelegate>& delegate);
 
  private:
   gvr::GvrApi* GetGvrApi();
 
-  GvrDelegate* delegate_;
+  base::WeakPtr<GvrDelegate> delegate_;
   GvrDeviceProvider* gvr_provider_;
-  bool secure_origin_;
+  bool secure_origin_ = false;
   uint32_t pose_index_ = 0;
 
   DISALLOW_COPY_AND_ASSIGN(GvrDevice);
 };
 
 }  // namespace device
 
 #endif  // DEVICE_VR_ANDROID_GVR_DEVICE_H