[gom] build-sys: Don't override already set EXTRA_DIST

[Bastien Nocera <hadess src gnome org>]

commit a615f5cc1da473a83f782ea7ee0dee45c2356837
Author: Christophe Fergeau <cfergeau redhat com>
Date:   Tue Feb 17 16:35:45 2015 +0100

    build-sys: Don't override already set EXTRA_DIST
    
    Makefile.tests initializes EXTRA_DIST to "", tests/Makefile.include sets
    it to a different value rather than appending to it.
    As Makefile.am is including both, this causes warnings from automake
    that we are trying to override EXTRA_DIST which was already set.
    Appending with += fixes this warning.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=740948

 tests/Makefile.include |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/tests/Makefile.include b/tests/Makefile.include
index 5c888ff..ff8fe11 100644
--- a/tests/Makefile.include
+++ b/tests/Makefile.include
@@ -55,4 +55,4 @@ test_gom_find_specific_SOURCES = tests/test-gom-find-specific.c
 test_gom_find_specific_CPPFLAGS = $(GIO_CFLAGS) $(GOBJECT_CFLAGS) $(WARN_CFLAGS)
 test_gom_find_specific_LDADD = $(GIO_LIBS) $(GOBJECT_LIBS) $(top_builddir)/libgom-1.0.la
 
-EXTRA_DIST = $(top_srcdir)/tests/grl-bookmarks.db $(top_srcdir)/tests/gnome.png
+EXTRA_DIST += tests/grl-bookmarks.db tests/gnome.png