Implement WebVR presentation pausing for VR Shell Menu Mode

device/vr/vr_device_manager.h

Index: device/vr/vr_device_manager.h
diff --git a/device/vr/vr_device_manager.h b/device/vr/vr_device_manager.h
index 2a3bc206dcd916391a4cc8821b476dd8fe1ca1bc..da645a1d98039252cd58af44c93120dfeb5d45b3 100644
--- a/device/vr/vr_device_manager.h
+++ b/device/vr/vr_device_manager.h
@@ -12,7 +12,7 @@
 #include <vector>
 
 #include "base/macros.h"
-#include "base/memory/linked_ptr.h"
+#include "base/memory/ref_counted.h"
 #include "base/threading/thread_checker.h"
 #include "base/timer/timer.h"
 #include "device/vr/vr_client_dispatcher.h"
@@ -55,6 +55,8 @@ class VRDeviceManager : public VRClientDispatcher {
   void OnDeviceConnectionStatusChanged(VRDevice* device,
                                        bool is_connected) override;
   void OnPresentEnded(VRDevice* device) override;
+  void OnDisplayBlur(VRDevice* device) override;
+  void OnDisplayFocus(VRDevice* device) override;
 
  private:
   friend class VRDeviceManagerTest;
@@ -62,8 +64,7 @@ class VRDeviceManager : public VRClientDispatcher {
 
   VRDeviceManager();
   // Constructor for testing.
-  DEVICE_VR_EXPORT explicit VRDeviceManager(
-      std::unique_ptr<VRDeviceProvider> provider);
+  DEVICE_VR_EXPORT explicit VRDeviceManager(VRDeviceProvider* provider);
 
   DEVICE_VR_EXPORT VRDevice* GetDevice(unsigned int index);
 
@@ -71,13 +72,13 @@ class VRDeviceManager : public VRClientDispatcher {
   static bool HasInstance();
 
   void InitializeProviders();
-  void RegisterProvider(std::unique_ptr<VRDeviceProvider> provider);
+  void RegisterProvider(VRDeviceProvider* provider);
 
   void SchedulePollEvents();
   void PollEvents();
   void StopSchedulingPollEvents();
 
-  using ProviderList = std::vector<linked_ptr<VRDeviceProvider>>;
+  using ProviderList = std::vector<scoped_refptr<VRDeviceProvider>>;
   ProviderList providers_;
 
   // Devices are owned by their providers.