[gtk+/native-layout] Avoid warnings when introspetion is not available

[Tristan Van Berkom <tvb src gnome org>]

commit 9242d1414d33c8a153e2ecb860f9710a1f670000
Author: Johan Dahlin <johan gnome org>
Date:   Thu Dec 31 01:47:24 2009 +0100

    Avoid warnings when introspetion is not available
    
    -include is the same as include but will never warn if the
    file is not available

 gdk-pixbuf/Makefile.am |    2 +-
 gdk/Makefile.am        |    2 +-
 gtk/Makefile.am        |    2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)
---
diff --git a/gdk-pixbuf/Makefile.am b/gdk-pixbuf/Makefile.am
index 7c2407b..58685dc 100644
--- a/gdk-pixbuf/Makefile.am
+++ b/gdk-pixbuf/Makefile.am
@@ -1,5 +1,5 @@
 include $(top_srcdir)/Makefile.decl
-include $(INTROSPECTION_MAKEFILE)
+-include $(INTROSPECTION_MAKEFILE)
 
 INTROSPECTION_GIRS =
 
diff --git a/gdk/Makefile.am b/gdk/Makefile.am
index 1d3ece4..7dfc193 100644
--- a/gdk/Makefile.am
+++ b/gdk/Makefile.am
@@ -1,6 +1,6 @@
 ## Makefile.am for gtk+/gdk
 include $(top_srcdir)/Makefile.decl
-include $(INTROSPECTION_MAKEFILE)
+-include $(INTROSPECTION_MAKEFILE)
 INTROSPECTION_GIRS =
 INTROSPECTION_SCANNER_ARGS = \
    --add-include-path=../gdk-pixbuf
diff --git a/gtk/Makefile.am b/gtk/Makefile.am
index 6374226..0d9784b 100644
--- a/gtk/Makefile.am
+++ b/gtk/Makefile.am
@@ -1,6 +1,6 @@
 # Makefile.am for gtk+/gtk
 include $(top_srcdir)/Makefile.decl
-include $(INTROSPECTION_MAKEFILE)
+-include $(INTROSPECTION_MAKEFILE)
 INTROSPECTION_GIRS =
 INTROSPECTION_SCANNER_ARGS = \
 	--add-include-path=../gdk-pixbuf \