[MIRROR] Makes emsisive blockers like, work [MDB IGNORE] (#20698)

* Makes emsisive blockers like, work (#74887)

## About The Pull Request

We assumed 0 meant no emissive blocker, but moth changed that a while
back, so post /atom/movable/Initialize generic emissive blockers just..
didn't work

Let's uh, fix that

Oh also makes pipes update their icon BEFORE they call update_icon
parent, so their emissive blockers look right

## Why It's Good For The Game

![image](https://user-images.githubusercontent.com/58055496/233563370-ddd95534-3a49-41f7-8aa8-5b1a001f4335.png)

Closes #74905

## Changelog
🆑
fix: Things that block glow will now like, do that again
/🆑

* Makes emsisive blockers like, work

---------

Co-authored-by: LemonInTheDark <58055496+LemonInTheDark@users.noreply.github.com>

code/modules/atmospherics/machinery/pipes/pipes.dm

@@ -105,9 +105,9 @@
 	icon_state = "[bitfield]_[piping_layer]"
 
 /obj/machinery/atmospherics/pipe/update_icon()
-	. = ..()
 	update_pipe_icon()
 	update_layer()
+	return ..()
 
 /obj/machinery/atmospherics/proc/update_node_icon()
 	for(var/i in 1 to device_type)