[gnome-shell] extensionPrefs: Scroll with key focus

[Georges Basile Stavracas Neto <gbsneto src gnome org>]

commit db85e7084cd02c8a168158d4d06c246bf6476b9c
Author: Florian Müllner <fmuellner gnome org>
Date:   Thu Jan 30 01:28:02 2020 +0100

    extensionPrefs: Scroll with key focus
    
    Currently when the extensions list is scrolled, it is possible to
    keynav out of view, as the scrolling doesn't follow the key focus.
    
    Hook up the adjustment to fix that.
    
    https://gitlab.gnome.org/GNOME/gnome-shell/issues/1968

 js/extensionPrefs/main.js                 | 4 ++++
 js/extensionPrefs/ui/extensions-window.ui | 4 ++--
 2 files changed, 6 insertions(+), 2 deletions(-)
---
diff --git a/js/extensionPrefs/main.js b/js/extensionPrefs/main.js
index 55172fb54a..74292957e1 100644
--- a/js/extensionPrefs/main.js
+++ b/js/extensionPrefs/main.js
@@ -70,7 +70,9 @@ var ExtensionsWindow = GObject.registerClass({
     InternalChildren: [
         'extensionsList',
         'killSwitch',
+        'mainBox',
         'mainStack',
+        'scrolledWindow',
     ],
 }, class ExtensionsWindow extends Gtk.ApplicationWindow {
     _init(params) {
@@ -80,6 +82,8 @@ var ExtensionsWindow = GObject.registerClass({
         this._loaded = false;
         this._prefsDialog = null;
 
+        this._mainBox.set_focus_vadjustment(this._scrolledWindow.vadjustment);
+
         this._settings = new Gio.Settings({ schema_id: 'org.gnome.shell' });
         this._settings.bind('disable-user-extensions',
             this._killSwitch, 'active',
diff --git a/js/extensionPrefs/ui/extensions-window.ui b/js/extensionPrefs/ui/extensions-window.ui
index 8c235f4a03..7305a03ee4 100644
--- a/js/extensionPrefs/ui/extensions-window.ui
+++ b/js/extensionPrefs/ui/extensions-window.ui
@@ -25,14 +25,14 @@
         <property name="visible">True</property>
         <property name="transition_type">crossfade</property>
         <child>
-          <object class="GtkScrolledWindow">
+          <object class="GtkScrolledWindow" id="scrolledWindow">
             <property name="visible">True</property>
             <property name="hscrollbar_policy">never</property>
             <child>
               <object class="GtkViewport">
                 <property name="visible">True</property>
                 <child>
-                  <object class="GtkBox">
+                  <object class="GtkBox" id="mainBox">
                     <property name="visible">True</property>
                     <property name="orientation">vertical</property>
                     <property name="halign">center</property>