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

chrome/browser/android/vr_shell/vr_shell_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_VR_SHELL_DELEGATE_H_
 #define CHROME_BROWSER_ANDROID_VR_SHELL_VR_SHELL_DELEGATE_H_
 
 #include <jni.h>
 
 #include <memory>
@@ skipping 32 matching lines @@
                         const base::android::JavaParamRef<jobject>& obj,
                         jboolean success);
   void DisplayActivate(JNIEnv* env,
                        const base::android::JavaParamRef<jobject>& obj);
   void UpdateVSyncInterval(JNIEnv* env,
                            const base::android::JavaParamRef<jobject>& obj,
                            jlong timebase_nanos,
                            jdouble interval_seconds);
   void OnPause(JNIEnv* env, const base::android::JavaParamRef<jobject>& obj);
   void OnResume(JNIEnv* env, const base::android::JavaParamRef<jobject>& obj);
+  void UpdateNonPresentingContext(
+      JNIEnv* env,
+      const base::android::JavaParamRef<jobject>& obj,
+      jlong context);
   void Destroy(JNIEnv* env, const base::android::JavaParamRef<jobject>& obj);
 
   device::GvrDeviceProvider* device_provider() { return device_provider_; }
 
   // device::GvrDelegateProvider implementation.
   void ExitWebVRPresent() override;
 
  private:
   // device::GvrDelegateProvider implementation.
   void SetDeviceProvider(device::GvrDeviceProvider* device_provider) override;
@@ skipping 20 matching lines @@
   base::WeakPtrFactory<VrShellDelegate> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(VrShellDelegate);
 };
 
 bool RegisterVrShellDelegate(JNIEnv* env);
 
 }  // namespace vr_shell
 
 #endif  // CHROME_BROWSER_ANDROID_VR_SHELL_VR_SHELL_DELEGATE_H_