includes/class-freemius.php
function add_filter( $tag, $function_to_add, $priority = WP_FS__DEFAULT_PRIORITY, $accepted_args = 1 ) {
            $this->_logger->entrance( $tag );

            add_filter( $this->get_action_tag( $tag ), $function_to_add, $priority, $accepted_args );
        }
function add_filter( $tag, $function_to_add, $priority = WP_FS__DEFAULT_PRIORITY, $accepted_args = 1 ) {
            $this->_logger->entrance( $tag );

            add_filter( $this->get_action_tag( $tag ), $function_to_add, $priority, $accepted_args );
        }
function add_filter ( $ tag , $ function_to_add , $ priority = WP_FS__DEFAULT_PRIORITY , $ accepted_args = 1 ) { $ this -> _logger -> entrance ( $ tag ) ; add_filter ( $ this -> get_action_tag ( $ tag ) , $ function_to_add , $ priority , $ accepted_args ) ; }
Add filter, specific for the current context plugin.

@author Vova Feldman (@svovaf)
@since  1.0.9

@param string   $tag
@param callable $function_to_add
@param int      $priority
@param int      $accepted_args

@uses   add_filter()
Add filter specific for the current context plugin .