WIP SanitizationHelperTrait: update for PHPCS 4.0

Need to check if this way is the best way to fix the problem and improve it (document, make more readable).

It seems the failing tests are failing because of is_in_function_call().

Author: rodrigoprimo

WordPress/Helpers/ArrayWalkingFunctionsHelper.php

@@ -71,7 +71,7 @@ public static function get_functions() {
 	 * @return bool
 	 */
 	public static function is_array_walking_function( $functionName ) {
-		return isset( self::$arrayWalkingFunctions[ strtolower( $functionName ) ] );
+		return isset( self::$arrayWalkingFunctions[ strtolower( ltrim( $functionName, '\\' ) ) ] );
 	}
 
 	/**

WordPress/Helpers/SanitizationHelperTrait.php

@@ -239,7 +239,7 @@ final public function get_sanitizing_and_unslashing_functions() {
 	 * @return bool
 	 */
 	final public function is_sanitizing_function( $functionName ) {
-		return isset( $this->get_sanitizing_functions()[ strtolower( $functionName ) ] );
+		return isset( $this->get_sanitizing_functions()[ strtolower( ltrim( $functionName, '\\' ) ) ] );
 	}
 
 	/**
@@ -252,7 +252,7 @@ final public function is_sanitizing_function( $functionName ) {
 	 * @return bool
 	 */
 	final public function is_sanitizing_and_unslashing_function( $functionName ) {
-		return isset( $this->get_sanitizing_and_unslashing_functions()[ strtolower( $functionName ) ] );
+		return isset( $this->get_sanitizing_and_unslashing_functions()[ strtolower( ltrim( $functionName, '\\' ) ) ] );
 	}
 
 	/**

WordPress/Helpers/UnslashingFunctionsHelper.php

@@ -54,6 +54,6 @@ public static function get_functions() {
 	 * @return bool
 	 */
 	public static function is_unslashing_function( $functionName ) {
-		return isset( self::$unslashingFunctions[ strtolower( $functionName ) ] );
+		return isset( self::$unslashingFunctions[ strtolower( ltrim( $functionName, '\\' ) ) ] );
 	}
 }