[dconf-editor] Improve row selection when browsing.

[Arnaud B. <arnaudb src gnome org>]

commit 725df7b3c2c2943c800911cd198f91863f114037
Author: Arnaud Bonatti <arnaud bonatti gmail com>
Date:   Sun Sep 23 16:46:27 2018 +0200

    Improve row selection when browsing.
    
    Selecting the first folder row when there is no keys and the
    new preferences row when there is at least one feels great.

 editor/registry-view.vala | 22 +++++++++++++++++++---
 1 file changed, 19 insertions(+), 3 deletions(-)
---
diff --git a/editor/registry-view.vala b/editor/registry-view.vala
index 5c29e14..9f0b5ce 100644
--- a/editor/registry-view.vala
+++ b/editor/registry-view.vala
@@ -90,9 +90,25 @@ private class RegistryView : RegistryList
 
     internal override void select_first_row ()
     {
-        ListBoxRow? row = key_list_box.get_row_at_index (0);
-        if (row != null)
-            scroll_to_row ((!) row, true);
+        uint n_items = list_model.get_n_items ();
+        if (n_items == 0)
+            assert_not_reached ();
+
+        ListBoxRow? row;
+        if (n_items == 1)
+            row = key_list_box.get_row_at_index (0);
+        else
+        {
+            SimpleSettingObject sso = (SimpleSettingObject) list_model.get_object (n_items - 1);
+
+            if (ModelUtils.is_folder_context_id (sso.context_id)) // if do not contain at least one key
+                row = key_list_box.get_row_at_index (1);
+            else
+                row = key_list_box.get_row_at_index (0);
+        }
+        if (row == null)
+            assert_not_reached ();
+        scroll_to_row ((!) row, true);
     }
 
     /*\