shell_util_normalize_and_casefold: New utility function

Merge the duplicated copies into shell-util.

src/shell-util.c

@@ -506,6 +506,20 @@ shell_util_get_transformed_allocation (ClutterActor    *actor,
   box->y2 = y_max;
 }
 
+char *
+shell_util_normalize_and_casefold (const char *str)
+{
+  char *normalized, *result;
+
+  if (str == NULL)
+    return NULL;
+
+  normalized = g_utf8_normalize (str, -1, G_NORMALIZE_ALL);
+  result = g_utf8_casefold (normalized, -1);
+  g_free (normalized);
+  return result;
+}
+
 /**
  * shell_util_format_date:
  * @format: a strftime-style string format, as parsed by