Fixed webxr_vr_paint "not painting" with left hand.

examples/webxr_vr_paint.html

@@ -85,7 +85,7 @@
 				scene.add( painter1.mesh );
 
 				painter2 = new TubePainter();
-				scene.add( painter1.mesh );
+				scene.add( painter2.mesh );
 
 				//