[gnome-shell] workspace: Fix an incorrect signal check

[Florian Müllner <fmuellner src gnome org>]

commit 48adb2ef4b3fa97c59952ca45918268e1e2d0160
Author: Jonas Dreßler <verdre v0yd nl>
Date:   Fri Sep 20 11:37:26 2019 +0200

    workspace: Fix an incorrect signal check
    
    While commit 3094f863 was intended to cancel the ongoing idle hide
    timeout before we start a new one, a mistake slipped in there while
    rebasing: Obviously we should check if the signal id is NOT 0 here.
    
    This didn't prevent timeouts being started while old ones are still
    running and did override `this._idleHideOverlayId`, which caused the old
    timeouts to run indefinitely after an overlay actor was destroyed
    because we fail early (and don't return TRUE) in `_idleHideOverlay()`.
    
    https://gitlab.gnome.org/GNOME/gnome-shell/merge_requests/735

 js/ui/workspace.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/js/ui/workspace.js b/js/ui/workspace.js
index 3177928320..a93b19add9 100644
--- a/js/ui/workspace.js
+++ b/js/ui/workspace.js
@@ -684,7 +684,7 @@ var WindowOverlay = class {
     }
 
     _onHideChrome() {
-        if (this._idleHideOverlayId == 0)
+        if (this._idleHideOverlayId > 0)
             GLib.source_remove(this._idleHideOverlayId);
 
         this._idleHideOverlayId = GLib.timeout_add(GLib.PRIORITY_DEFAULT, WINDOW_OVERLAY_IDLE_HIDE_TIMEOUT, 
this._idleHideOverlay.bind(this));