Handle getVRDisplays rejection for the case where the API is present, but WebVR is not supported

examples/js/vr/WebVR.js

@@ -32,6 +32,10 @@ var WEBVR = {
 
 					}
 
+				}, function () {
+
+					reject( 'Your browser does not support WebVR. See <a href="https://webvr.info">webvr.info</a> for assistance.' );
+				
 				} );
 
 			} else {