[gnome-shell] extensionSystem: Add missing return value

[Florian Müllner <fmuellner src gnome org>]

commit ce9227062635804a347cf214cf370d24bf39c624
Author: Florian Müllner <fmuellner gnome org>
Date:   Thu Sep 12 12:40:46 2019 +0200

    extensionSystem: Add missing return value
    
    _callExtensionInit() should return whether the extension was initialized
    successfully or not, but the early return added in commit 2a9e065cfb
    doesn't.
    
    https://gitlab.gnome.org/GNOME/gnome-shell/merge_requests/715

 js/ui/extensionSystem.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/js/ui/extensionSystem.js b/js/ui/extensionSystem.js
index 7fe275ec7b..e8f2079437 100644
--- a/js/ui/extensionSystem.js
+++ b/js/ui/extensionSystem.js
@@ -305,7 +305,7 @@ var ExtensionManager = class {
 
     _callExtensionInit(uuid) {
         if (!Main.sessionMode.allowExtensions)
-            return;
+            return false;
 
         let extension = this.lookup(uuid);
         if (!extension)