Fixed bug in php7+ with symfony < 3.3

PHP7 raised an warning when non-numeric values were used in bitwise operations (e.g. $foo | $bar where $foo or $bar was not a numeric value).

This resulted in a thrown ErrorException within Laravel.

This fixes that by returning out of the function before the bitwise calculation is complete, under the assumption that that condition only happens when Symfony < 3.3.