Refactor GvrDelegate ownership into GvrDelegateProvider and fix more threading violations.

device/vr/test/fake_vr_device.h

 // Copyright 2015 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_TEST_FAKE_VR_DEVICE_H_
 #define DEVICE_VR_TEST_FAKE_VR_DEVICE_H_
 
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "device/vr/vr_device.h"
 #include "device/vr/vr_device_provider.h"
 #include "device/vr/vr_service_impl.h"
 
 namespace device {
 
 class FakeVRDevice : public VRDevice {
  public:
   explicit FakeVRDevice();
   ~FakeVRDevice() override;
 
   void InitBasicDevice();
 
   void SetVRDevice(const mojom::VRDisplayInfoPtr& device);
 
-  mojom::VRDisplayInfoPtr GetVRDevice() override;
+  // VRDevice
+  void GetVRDevice(
+      const base::Callback<void(mojom::VRDisplayInfoPtr)>& callback) override;
   void ResetPose() override;
 
   void RequestPresent(const base::Callback<void(bool)>& callback) override;
   void SetSecureOrigin(bool secure_origin) override;
   void ExitPresent() override;
   void SubmitFrame(mojom::VRPosePtr pose) override;
   void UpdateLayerBounds(int16_t frame_index,
                          mojom::VRLayerBoundsPtr leftBounds,
                          mojom::VRLayerBoundsPtr rightBounds) override;
   void GetVRVSyncProvider(mojom::VRVSyncProviderRequest request) override;
 
  private:
   mojom::VREyeParametersPtr InitEye(float fov, float offset, uint32_t size);
 
   mojom::VRDisplayInfoPtr device_;
 
   DISALLOW_COPY_AND_ASSIGN(FakeVRDevice);
 };
 
 }  // namespace device
 
 #endif  // DEVICE_VR_TEST_FAKE_VR_DEVICE_H_