plack/Plack — pull request #474 by nwellnhof (2014-10-18 13:52:46+00:00)
Title: Fix content filter in ErrorDocument

The content filter in ErrorDocument never set the $done variable to a
true value in the non-subrequest case. As a result, it kept returning
empty strings at the end of input, not undef like it should. This is
actually harmless because response_cb copes with this behavior.