I find most uses of array_filter(), array_reduce(), etc. to be
excessively clever, i.e. they are used to prove how smart the
developer is, at the expense of readability and performance. So I am
pleased to have a defensible reason to remove these instances, which
broke PHPStorm's type propagation.
Change-Id: I03dcd6c3c80f19f90e7b39448b5508713da63806
