[gimp] Workaround for intltool vs. automake issue during distcheck

[Michael Schumacher <schumaml src gnome org>]

commit c960069198bc4137fbd64a3fdf75ad0449a5f64e
Author: Michael Schumacher <schumaml gmx de>
Date:   Fri Aug 21 00:42:10 2015 +0200

    Workaround for intltool vs. automake issue  during distcheck
    
    intltool and automake 1.15 currently cause a problem during make distcheck.
    This is a no-op workaround for intltool-update to make that succeed again.
    See https://github.com/systemd/systemd/commit/06528e8fdd and
    https://bugs.launchpad.net/intltool/+bug/1117944 for more information.
    
    Thanks to Daniel Mack for pointing this out during Chaos Communication Camp.

 configure.ac |    5 +++++
 1 files changed, 5 insertions(+), 0 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index 5748aa9..f29a5a4 100644
--- a/configure.ac
+++ b/configure.ac
@@ -212,6 +212,11 @@ AC_SUBST(GETTEXT_PACKAGE)
 AC_DEFINE_UNQUOTED(GETTEXT_PACKAGE, "$GETTEXT_PACKAGE",
                    [The prefix for our gettext translation domains.])
 
+# work around intltool-update issues during 'make distcheck'
+AS_IF([test "x$0" != "x./configure"], [
+        AC_SUBST([INTLTOOL_UPDATE], [/bin/true])
+])
+
 # Determine a C compiler to use
 AC_PROG_CC
 AM_PROG_CC_C_O