Do not output (null) for missing icons

Author: johanmalm

Diff for: main.c

@@ -92,7 +92,7 @@ print_app_to_buffer(struct app *app, GString *submenu)
 	g_string_append_printf(submenu, "    <item label=\"%s\"",
 		app->name_localized ? app->name_localized : app->name);
 	if (show_icons) {
-		g_string_append_printf(submenu, " icon=\"%s\"", app->icon);
+		g_string_append_printf(submenu, " icon=\"%s\"", app->icon ? app->icon : "");
 	}
 	g_string_append_printf(submenu, ">\n");
 
@@ -208,7 +208,7 @@ print_menu(GList *dirs, GList *apps)
 
 		printf("  <menu id=\"%s\" label=\"%s\"", dir->name, dir->name_localized ? : dir->name);
 		if (show_icons) {
-			printf(" icon=\"%s\"", dir->icon);
+			printf(" icon=\"%s\"", dir->icon ? dir->icon : "");
 		}
 		printf(">\n");