[gnome-control-center/wip/iainl/network-fix-apply] network: Accept empty values for the cloned mac address

[Iain Lane <iainl src gnome org>]

commit e4508e013089cf788fd7386e189b311bdedd88e0
Author: Iain Lane <iainl gnome org>
Date:   Sat Oct 5 11:57:48 2019 +0100

    network: Accept empty values for the cloned mac address
    
    Empty is a valid value here. It means the setting is not set. Two places
    need to be updated:
    
      - the validation function
      - when retrieving the value from the combo, empty strings need to be
        mapped to a setting value of NULL
    
    Closes #677

 panels/network/connection-editor/ce-page.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)
---
diff --git a/panels/network/connection-editor/ce-page.c b/panels/network/connection-editor/ce-page.c
index 4059ad328..adec1ae10 100644
--- a/panels/network/connection-editor/ce-page.c
+++ b/panels/network/connection-editor/ce-page.c
@@ -416,13 +416,19 @@ ce_page_setup_cloned_mac_combo (GtkComboBoxText *combo, const char *current)
 char *
 ce_page_cloned_mac_get (GtkComboBoxText *combo)
 {
+       g_autofree gchar *active_text = NULL;
        const char *id;
 
        id = gtk_combo_box_get_active_id (GTK_COMBO_BOX (combo));
        if (id)
                return g_strdup (id);
 
-       return gtk_combo_box_text_get_active_text (combo);
+       active_text = gtk_combo_box_text_get_active_text (combo);
+
+       if (active_text[0] == '\0')
+               return NULL;
+
+       return g_steal_pointer (&active_text);
 }
 
 gboolean
@@ -471,7 +477,7 @@ ce_page_cloned_mac_combo_valid (GtkComboBoxText *combo)
 
        active_text = gtk_combo_box_text_get_active_text (combo);
 
-       return ce_page_address_is_valid (active_text);
+       return active_text[0] == '\0' || ce_page_address_is_valid (active_text);
 }
 
 const gchar *