Stay in VR while showing DOFF flow and connect CCT exit button to this.

chrome/browser/android/vr_shell/non_presenting_gvr_delegate.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 CHROME_BROWSER_ANDROID_VR_SHELL_NON_PRESENTING_GVR_DELEGATE_H_
 #define CHROME_BROWSER_ANDROID_VR_SHELL_NON_PRESENTING_GVR_DELEGATE_H_
 
 #include <jni.h>
 
 #include <memory>
@@ skipping 29 matching lines @@
                            double interval_seconds) override;
 
   void CreateVRDisplayInfo(
       const base::Callback<void(device::mojom::VRDisplayInfoPtr)>& callback,
       uint32_t device_id) override;
 
   void Pause();
   void Resume();
   device::mojom::VRVSyncProviderRequest OnSwitchToPresentingDelegate();
 
+  void UpdateContext(gvr_context* context);
+
  private:
   void StopVSyncLoop();
   void StartVSyncLoop();
   void OnVSync();
   void SendVSync(base::TimeDelta time, const GetVSyncCallback& callback);
 
   // VRVSyncProvider implementation
   void GetVSync(const GetVSyncCallback& callback) override;
 
   std::unique_ptr<gvr::GvrApi> gvr_api_;
   scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
   base::CancelableClosure vsync_task_;
   base::TimeTicks vsync_timebase_;
   base::TimeDelta vsync_interval_;
 
   // Whether the vsync loop is paused, but not stopped.
   bool vsync_paused_ = false;
   base::TimeDelta pending_time_;
   bool pending_vsync_ = false;
   GetVSyncCallback callback_;
   mojo::Binding<device::mojom::VRVSyncProvider> binding_;
   base::WeakPtrFactory<NonPresentingGvrDelegate> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(NonPresentingGvrDelegate);
 };
 
 }  // namespace vr_shell
 
 #endif  // CHROME_BROWSER_ANDROID_VR_SHELL_NON_PRESENTING_GVR_DELEGATE_H_