diff --git a/WordPress/AbstractFunctionRestrictionsSniff.php b/WordPress/AbstractFunctionRestrictionsSniff.php
index 6a56d623ea..513d35a6e7 100644
--- a/WordPress/AbstractFunctionRestrictionsSniff.php
+++ b/WordPress/AbstractFunctionRestrictionsSniff.php
@@ -68,51 +68,6 @@ abstract class WordPress_AbstractFunctionRestrictionsSniff extends WordPress_Sni
 	 */
 	protected $excluded_groups = array();
 
-	/**
-	 * List of known PHP and WP functions which take a callback as an argument.
-	 *
-	 * Sorted alphabetically. Last updated on 8th March 2017.
-	 *
-	 * @since 0.11.0
-	 *
-	 * @var array <string function name> => <int callback argument position>
-	 */
-	protected $callback_functions = array(
-		'add_filter'                  => array( 2 ),
-		'add_action'                  => array( 2 ),
-		'array_diff_uassoc'           => array( -1 ), // = last argument passed.
-		'array_diff_ukey'             => array( -1 ), // = last argument passed.
-		'array_filter'                => array( 2 ),
-		'array_intersect_uassoc'      => array( -1 ), // = last argument passed.
-		'array_intersect_ukey'        => array( -1 ), // = last argument passed.
-		'array_map'                   => array( 1 ),
-		'array_reduce'                => array( 2 ),
-		'array_udiff_assoc'           => array( -1 ), // = last argument passed.
-		'array_udiff_uassoc'          => array( -1, -2 ), // = last argument passed.
-		'array_udiff'                 => array( -1 ), // = last argument passed.
-		'array_uintersect_assoc'      => array( -1 ), // = last argument passed.
-		'array_uintersect_uassoc'     => array( -1, -2 ), // = last argument passed.
-		'array_uintersect'            => array( -1 ), // = last argument passed.
-		'array_walk'                  => array( 2 ),
-		'array_walk_recursive'        => array( 2 ),
-		'call_user_func'              => array( 1 ),
-		'call_user_func_array'        => array( 1 ),
-		'forward_static_call'         => array( 1 ),
-		'forward_static_call_array'   => array( 1 ),
-		'header_register_callback'    => array( 1 ),
-		'iterator_apply'              => array( 2 ),
-		'mb_ereg_replace_callback'    => array( 2 ),
-		'ob_start'                    => array( 1 ),
-		'preg_replace_callback'       => array( 2 ),
-		'register_shutdown_function'  => array( 1 ),
-		'register_tick_function'      => array( 1 ),
-		'set_error_handler'           => array( 1 ),
-		'set_exception_handler'       => array( 1 ),
-		'uasort'                      => array( 2 ),
-		'uksort'                      => array( 2 ),
-		'usort'                       => array( 2 ),
-	);
-
 	/**
 	 * Groups of functions to restrict.
 	 *
@@ -281,7 +236,7 @@ public function is_targetted_token( $stackPtr ) {
 	 *                  normal file processing.
 	 */
 	public function check_for_matches( $stackPtr ) {
-		$token_content = strtolower( $this->strip_quotes( $this->tokens[ $stackPtr ]['content'] ) );
+		$token_content = strtolower( $this->tokens[ $stackPtr ]['content'] );
 		$skip_to       = array();
 
 		foreach ( $this->groups as $groupName => $group ) {
@@ -314,7 +269,7 @@ public function check_for_matches( $stackPtr ) {
 	 *
 	 * @param int $stackPtr The position of the current token in the stack.
 	 *
-	 * @return int|void If a callback was found return stackPtr for where to skip to, false if the function call is not a callback.
+	 * @return int|void If a callback was found return stackPtr for where to skip to.
 	 */
 	public function check_for_callback_matches( $stackPtr ) {
 
@@ -354,7 +309,7 @@ public function check_for_callback_matches( $stackPtr ) {
 				return;
 			}
 
-			$skip_to[] = $this->check_for_matches( $callback );
+			$skip_to[] = $this->check_for_matches( $this->strip_quotes( $callback ) );
 		}
 
 		if ( empty( $skip_to ) || min( $skip_to ) === 0 ) {