Debian packaging: drop fish-common package

Splitting fish into multiple packages was what the downstream Debian
packaging does, but it provides minimal benefit to end-users installing
from the fish repositories and in some cases made it harder. The only
benefit was a slightly reduced size on disk for download repositories.

Closes #7845.

Reverts 45ae726d4f and solves #3053
through a Conflict with fish-common.

debian/control

@@ -13,27 +13,16 @@ Vcs-Browser: https://github.com/fish-shell/fish-shell
 
 Package: fish
 Architecture: any
-Depends: ${shlibs:Depends}, ${misc:Depends}, fish-common (= ${source:Version}), passwd (>= 4.0.3-10), gettext-base, man-db
+Depends: ${shlibs:Depends}, ${misc:Depends}, passwd (>= 4.0.3-10), gettext-base, man-db,
+ python3 (>=3.5)
+Conflicts: fish-common
 Recommends: xsel (>=1.2.0)
+Suggests: xdg-utils
 Description: friendly interactive shell
  Fish is a command-line shell for modern systems, focusing on user-friendliness,
  sensibility and discoverability in interactive use. The syntax is simple, but
  not POSIX compliant.
 
-Package: fish-common
-Architecture: all
-Multi-Arch: foreign
-Depends: ${misc:Depends}
-Recommends: fish, python3 (>= 3.5)
-Suggests: xdg-utils
-Replaces: fish (<= 2.1.1.dfsg-2)
-Description: friendly interactive shell (architecture-independent files)
- Fish is a command-line shell for modern systems, focusing on user-friendliness,
- sensibility and discoverability in interactive use. The syntax is simple, but
- not POSIX compliant.
- .
- This package contains the common fish files shared by all architectures.
-
 Package: fish-dbg
 Architecture: any
 Section: debug

debian/fish-common.install

@@ -1,2 +0,0 @@
-debian/tmp/etc
-debian/tmp/usr/share

debian/fish-common.lintian-overrides

@@ -1,4 +0,0 @@
-# These directories are intentionally empty.
-fish-common: package-contains-empty-directory usr/share/fish/vendor_completions.d/
-fish-common: package-contains-empty-directory usr/share/fish/vendor_conf.d/
-fish-common: package-contains-empty-directory usr/share/fish/vendor_functions.d/

debian/fish.install

@@ -1 +1,3 @@
 debian/tmp/usr/bin
+debian/tmp/etc
+debian/tmp/usr/share

debian/fish.lintian-overrides

@@ -0,0 +1,4 @@
+# These directories are intentionally empty.
+fish: package-contains-empty-directory usr/share/fish/vendor_completions.d/
+fish: package-contains-empty-directory usr/share/fish/vendor_conf.d/
+fish: package-contains-empty-directory usr/share/fish/vendor_functions.d/

debian/rules

@@ -16,9 +16,6 @@ override_dh_auto_configure:
 override_dh_auto_build:
 	dh_auto_build -- all fish_tests tests_buildroot_target
 
-override_dh_installdocs:
-	dh_installdocs --link-doc=fish
-
 # Still needed until all platforms have debhelper 9.20151219
 # Consider transitioning https://wiki.debian.org/DebugPackage
 override_dh_strip: