After initializing a filter, we try to read from it to

After initializing a filter, we try to read from it to
verify that it's working (in particular, this gives early
error reporting when external decompression programs are
nonexistent or exit immediately).  If this read failed,
we weren't properly cleaning up the just-initialized filter.
Since this is fatal, the easiest fix is to refactor the close()
handler and just release the entire filter chain.

SVN-Revision: 1790