Bug#563121: dh_installdefoma leads to buggy maintainer scripts

[Cyril Brulebois <kibi@debian.org>]

Package: defoma
Version: 0.11.10-3
Severity: grave
Justification: Fucks up fontconfig (at least), then buildds.

Hi,

dh_installdefoma leads to this kind of code in maintainer scripts:
  test -x `which foo` && foo bar baz

The trick being that if foo isn't found by which, “foo bar baz” gets
executed, leading to broken packages (see fontconfig's #559136 and
#560252 for examples).

A pair of quotes would fix this:
| kibi@finzi:~$ test -x `which foo` && foo bar baz
| -bash: foo: command not found
| kibi@finzi:~$ test -x "`which foo`" && foo bar baz
| kibi@finzi:~$ 

I'm about to QA-upload defoma with this change in the various
debhelper-files/* files, but I wanted to open this bugreport for
reference.

Cc'ing defoma folks and buildd folks, since they might be interested in
knowing about this.

Mraw,
KiBi.