Bug#759213: lintian: quilt-build-dep-but-no-series-file triggered even if debian/patches/series exists (but empty)

[Axel Beckert <abe@debian.org>]

Package: lintian
Version: 2.5.25
Severity: normal

Dear Lintian Hackers,

for format 1.0 source packages which occassionally need patching, I
prefer to keep quilt in the build-dependencies and
debian/rules. I also keep an empty debian/patches/series file.

But lintian still claims quilt-build-dep-but-no-series-file despite it
is surely not true that there is no series file.

So please suppress this warning if debian/patches/series is empty as
this is a sign that this was done deliberately.

In case you think there still could be cases where an empty
debian/patches/series file is not on purpose, feel free to add a
separate, maybe pedantic-level warning about that.

TIA!

P.S.: Soon to be uploaded test case: t-prot 3.2-1

-- System Information:
Debian Release: jessie/sid
  APT prefers unstable
  APT policy: (990, 'unstable'), (600, 'testing'), (110, 'experimental'), (109, 'buildd-unstable')
Architecture: amd64 (x86_64)

Kernel: Linux 3.15-trunk-amd64 (SMP w/4 CPU cores)
Locale: LANG=C.UTF-8, LC_CTYPE=C.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash

Versions of packages lintian depends on:
ii  binutils                       2.24.51.20140818-1
ii  bzip2                          1.0.6-7
ii  diffstat                       1.58-1
ii  file                           1:5.19-1
ii  gettext                        0.19.2-1
ii  hardening-includes             2.5+nmu1
ii  intltool-debian                0.35.0+20060710.1
ii  libapt-pkg-perl                0.1.29+b2
ii  libarchive-zip-perl            1.37-2
ii  libclass-accessor-perl         0.34-1
ii  libclone-perl                  0.37-1+b1
ii  libdpkg-perl                   1.17.13
ii  libemail-valid-perl            1.194-1
ii  libfile-basedir-perl           0.03-1
ii  libipc-run-perl                0.92-1
ii  liblist-moreutils-perl         0.33-2+b1
ii  libparse-debianchangelog-perl  1.2.0-1
ii  libtext-levenshtein-perl       0.09-1
ii  libtimedate-perl               2.3000-2
ii  liburi-perl                    1.64-1
ii  man-db                         2.6.7.1-1
ii  patchutils                     0.3.3-1
ii  perl [libdigest-sha-perl]      5.20.0-4
ii  t1utils                        1.37-2

Versions of packages lintian recommends:
ii  libautodie-perl                 2.25-1
ii  libperlio-gzip-perl             0.18-3+b1
ii  perl-modules [libautodie-perl]  5.20.0-4

Versions of packages lintian suggests:
pn  binutils-multiarch     <none>
ii  dpkg-dev               1.17.13
ii  libhtml-parser-perl    3.71-1+b2
ii  libtext-template-perl  1.46-1
ii  libyaml-perl           1.01-1
ii  xz-utils               5.1.1alpha+20120614-2

-- no debconf information