WebXRManager: Clean up.

src/renderers/webvr/WebXRManager.js

@@ -14,7 +14,6 @@ function WebXRManager( renderer ) {
 	var session = null;
 
 	var frameOfRef = null;
-	var isExclusive = false;
 
 	var pose = null;
 
@@ -75,7 +74,6 @@ function WebXRManager( renderer ) {
 			session.requestFrameOfReference( 'stage' ).then( function ( value ) {
 
 				frameOfRef = value;
-				isExclusive = session.exclusive;
 
 				renderer.setFramebuffer( session.baseLayer.framebuffer );
 
@@ -155,8 +153,6 @@ function WebXRManager( renderer ) {
 
 	};
 
-	this.requestAnimationFrame = function () {};
-
 	this.submitFrame = function () {};
 
 }