Relocate calls to func_get_args() to beginnings of functions

On account of the backwards-incompatible changes made in PHP 7.0, it's helpful to move any calls to func_get_arg() and func_get_args() to the start of the function (even when the original location was safe in practice), in order to reduce cognitive load for the reader.

Making this change can also eliminate warnings (sometimes false-positive) from certain code linters. e.g. "[Warning] Function argument(s) returned by "func_get_args" might have been modified."

Refer to https://secure.php.net/manual/en/migration70.incompatible.php#migration7...