[mutter] Generate marshallers without including the generated header

[Emmanuele Bassi <ebassi src gnome org>]

commit 9131f26caedb9fda7a562363215889920ebaf354
Author: Emmanuele Bassi <ebassi gnome org>
Date:   Sun Apr 30 14:55:20 2017 +0100

    Generate marshallers without including the generated header
    
    GLib now generates the prototypes for the generated marshallers, so it's
    not necessary to include the header any more.
    
    This fixes a build failure in GNOME Continuous with GLib master, caused
    by -Werror=redundant-decls.

 clutter/clutter/Makefile.am.marshal |    7 +++----
 1 files changed, 3 insertions(+), 4 deletions(-)
---
diff --git a/clutter/clutter/Makefile.am.marshal b/clutter/clutter/Makefile.am.marshal
index 89d3222..b6fc896 100644
--- a/clutter/clutter/Makefile.am.marshal
+++ b/clutter/clutter/Makefile.am.marshal
@@ -43,10 +43,9 @@ $(marshal_h): stamp-marshal
        @true
 
 $(marshal_c): $(marshal_h)
-       $(AM_V_GEN)(echo "#include \"$(marshal_h)\"" ; \
-       $(GLIB_GENMARSHAL) \
+       $(AM_V_GEN)$(GLIB_GENMARSHAL)
                --prefix=$(glib_marshal_prefix) \
                --body \
-       $(marshal_list)) > xgen-mc \
-       && cp xgen-mc $(marshal_c) \
+       $(marshal_list) > xgen-mc \
+       && (cmp -s xgen-mc $(marshal_c) || cp -f xgen-mc $(marshal_c)) \
        && rm -f xgen-mc