[ticket/12056] h_radio test: Fix "Creating default object from empty value"

PHPBB3-12056
[ticket/12056] build_select: Fix "Creating default object from empty value"

PHPBB3-12056
[ticket/12056] validate_range: Fix "Creating default object from empty value"

PHPBB3-12056
[ticket/12056] validate_config_vars: Fix "Creating ... from empty value".

PHPBB3-12056
[ticket/12056] validate_config_vars: Fix ".. undefined function utf8_strlen()"

PHPBB3-12056
[ticket/12056] Fix "undefined function phpbb_pcre_utf8_support()".

PHPBB3-12056
[ticket/12056] Fix "Call to undefined function phpbb\phpbb_get_plural_form()".

PHPBB3-12056
[ticket/12056] Fix "Call to a member function trigger_event() on a non-object".

PHPBB3-12056
[ticket/12056] Fix "Call to undefined function ...\utf8_clean_string()"

PHPBB3-12056
[ticket/12056] Fix "Call to undefined function ...\utf8_normalize_nfc()"

PHPBB3-12056
[ticket/12056] group_user_attributes: Fix "Creating ... from empty value".

PHPBB3-12056
Merge remote-tracking branch 'bantu/ticket/12056-develop' into develop

* bantu/ticket/12056-develop:
  [ticket/12056] group_user_attributes: Fix "Creating ... from empty value".
  [ticket/12056] Fix "Call to undefined function ...\utf8_normalize_nfc()"
  [ticket/12056] Fix "Call to undefined function ...\utf8_clean_string()"
  [ticket/12056] Fix "Call to a member function trigger_event() on a non-object".
  [ticket/12056] Fix "Call to undefined function phpbb\phpbb_get_plural_form()".
  [ticket/12056] Fix "undefined function phpbb_pcre_utf8_support()".
  [ticket/12056] validate_config_vars: Fix ".. undefined function utf8_strlen()"
  [ticket/12056] validate_config_vars: Fix "Creating ... from empty value".
  [ticket/12056] validate_range: Fix "Creating default object from empty value"
  [ticket/12056] build_select: Fix "Creating default object from empty value"
  [ticket/12056] h_radio test: Fix "Creating default object from empty value"