Hide tool preview immediately when canceling

Previously you had to move the mouse for the tool preview to hide after you hit Esc or pressed two mouse buttons while using Free-Form Select.

src/functions.js

@@ -763,6 +763,7 @@ function cancel(){
 	);
 	if(!passive){ undo(); }
 	$G.triggerHandler("pointerup", "cancel");
+	update_helper_layer();
 }
 function this_ones_a_frame_changer(){
 	deselect();