Those darn gdk-pixbuf .po file conflicts

[Owen Taylor <otaylor redhat com>]

Anybody jhbuilding GNOME will have run into problems with .po file
conflicts in gdk-pixbuf, where building it causes local changes that
conflict with updates from translators. Finally got annoyed enough to
track down the problem.

The unique characteristics that gdk-pixbuf has that causes these
problems are:

 * It uses the upstream gettext Makefile.in.in not the GLib
   Makefile.in.in or the intltool Makefile.in.in

 * The .pot file isn't checked into Git

The upstream Makefile.in.in is designed so that when the .pot file isn't
there, it's generated, and the .po files are updated a single time.

(The upstream Makefile.in.in also has another incompatibility with
the GNOME internationalization workflow - it runs update-po on 'make
dist')

Possible fixes:

 A) Check in a .pot file. But this leaves the 'update-po on dist'
    problem. [This is the state of affairs of Clutter]

 B) intltoolize gdk-pixbuf, even though it doesn't need anything, so we
    get a non-annoying Makefile.in.in. [This is the most common
    thing in GNOME probably]
   
 C) Don't intltoolize gdk-pixbuf, but check some better
    Makefile.in.in into git so autopoint doesn't replace it.
   [This is the state of affairs in GTK+. Just copying the
   Makefile.in.in from GTK+ would presumably work fine.]

B) is probably cleanest; I don't know if it will cause problems for
people [cross]building gdk-pixbuf with mingw or building on OS X.

I haven't suggested going back to glib-gettextize, since that's been
something people have been trying to get away from. 

- Owen