Solved failing test in ArrayObject tests
Solved failing test in ArrayObject tests

- changed a typehint from "ArrayObject" to "self"

akrabat/zend-stdlib,MadCat34/zend-stdlib,sravanchandj/zend-stdlib,ezimuel/zend-stdlib,adamlundrigan/zend-stdlib,php-refactoring/zend-array-utility,weierophinney/zend-stdlib