WP_Widget_Categories::widget(): use int or bool for $cat_args values instead of numeric strings

[marian1]

Both $cat_args['show_count'] and $cat_args['hierarchical'] are currently set to '0' or '1' (numeric strings). See ​lines 54 to 68 in class-wp-widget-categories.php. These values are then passed to wp_dropdown_categories() or wp_list_categories(), both of which are documented to expect int|bool for $cat_args['show_count'] and $cat_args['hierarchical']. See the function references for ​wp_list_categories and ​wp_dropdown_categories.

As using integers or booleans instead of numeric strings does not alter the behaviour of WP_Widget_Categories::widget(), specifying $cat_args['show_count'] and $cat_args['hierarchical'] either as booleans or integers would increase type consistency.

Also, $dropdown (line 56) is set to '0' or '1' and could be set to true or false instead.

Trac ticket: https://core.trac.wordpress.org/ticket/62762