mootools/prime — pull request #3 by arian (2012-03-16 16:00:12+00:00)
Title: Fixes Array.filter ES5 mootools/mootools-core#2169.

As per spec, `Array.filter` should return the filtered items, and not
andany possible mutation that might have occurred in the callback. See
referenced issue for more information.

Added coverage for case.