[shotwell] Fix spacing for flagged button

[Jens Georg <jensgeorg src gnome org>]

commit 11dd2b4c2536185ce324294ed62cb45888a6c9a4
Author: Jens Georg <mail jensge org>
Date:   Sat Apr 14 18:19:32 2018 +0200

    Fix spacing for flagged button

 src/SearchFilter.vala |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)
---
diff --git a/src/SearchFilter.vala b/src/SearchFilter.vala
index 8d9aff1..44f5b34 100644
--- a/src/SearchFilter.vala
+++ b/src/SearchFilter.vala
@@ -644,6 +644,9 @@ public class SearchFilterToolbar : Gtk.Revealer {
             button.set_always_show_image(true);
             image = new Gtk.Image.from_icon_name(icon_name, Gtk.IconSize.SMALL_TOOLBAR);
             button.set_image(image);
+            if (button.get_label() != "" && button.get_label() != null) {
+                image.margin_end = 6;
+            }
         }
 
         public void set_label(string label) {