[nautilus] list-view: Add expander padding explanation

[Carlos Soriano <csoriano src gnome org>]

commit 1e8be8b5278439f7cbb48e158d84d86c7cc3f665
Author: Alexandru Fazakas <alex fazakas97 yahoo com>
Date:   Fri Feb 23 22:55:05 2018 +0200

    list-view: Add expander padding explanation
    
    With the new change on the expander padding, following contributors may have
    difficulties understanding how it works or why it had been changed.
    
    We added a link directing to @antoniof's explanation and fixed a typo regarding
    the change.
    
    Related to: https://gitlab.gnome.org/GNOME/nautilus/merge_requests/97

 src/nautilus-list-view.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)
---
diff --git a/src/nautilus-list-view.c b/src/nautilus-list-view.c
index 304a56eb0..166bd67c4 100644
--- a/src/nautilus-list-view.c
+++ b/src/nautilus-list-view.c
@@ -603,7 +603,9 @@ button_press_callback (GtkWidget      *widget,
 
         gtk_tree_view_get_cell_area (tree_view, path, column, &cell_area);
 
-        /* We assume that the cell area exclude the expander itself. */
+        /* We assume that the cell area excludes the expander itself. 
+         * Explanatory link for future reference: 
+         * https://gitlab.gnome.org/GNOME/nautilus/merge_requests/97#note_58649 */
 
         if (gtk_widget_get_direction (widget) == GTK_TEXT_DIR_RTL)
         {