Switch tabs from VR shell.

chrome/browser/android/vr_shell/vr_shell_delegate.h

Index: chrome/browser/android/vr_shell/vr_shell_delegate.h
diff --git a/chrome/browser/android/vr_shell/vr_shell_delegate.h b/chrome/browser/android/vr_shell/vr_shell_delegate.h
index af7b99a7557991250a83d2919e321a0cf87df283..cf55aaa9456a4a4b76513fc27861456333dd2a04 100644
--- a/chrome/browser/android/vr_shell/vr_shell_delegate.h
+++ b/chrome/browser/android/vr_shell/vr_shell_delegate.h
@@ -41,6 +41,7 @@ class VrShellDelegate : public device::GvrDelegateProvider {
                            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 ShowTab(int id);
 
   device::GvrDeviceProvider* device_provider() { return device_provider_; }
   void OnVRVsyncProviderRequest(device::mojom::VRVSyncProviderRequest request);