[gnome-shell] thunderbolt: fix missing variable underscore for `enrolling`

[Carlos Garnacho <carlosg src gnome org>]

commit 616852cf2b1f235a5671013fbf3f1564be79ea1b
Author: RyuzakiKK <aasonykk gmail com>
Date:   Fri Dec 7 10:51:39 2018 +0100

    thunderbolt: fix missing variable underscore for `enrolling`
    
    The variable `this.enrolling` is a typo because it has not been defined
    before and is also never used.
    `this._enrolling` is what it was meant to be.

 js/ui/status/thunderbolt.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/js/ui/status/thunderbolt.js b/js/ui/status/thunderbolt.js
index 4584748ed..3d7a9614a 100644
--- a/js/ui/status/thunderbolt.js
+++ b/js/ui/status/thunderbolt.js
@@ -195,7 +195,7 @@ var AuthRobot = new Lang.Class({
        if (this._enrolling)
            return;
 
-       this.enrolling = true;
+       this._enrolling = true;
        GLib.idle_add(GLib.PRIORITY_DEFAULT,
                      this._enrollDevicesIdle.bind(this));
     },