[gnome-shell] build: Use $(NULL) terminator for data files

[Florian Müllner <fmuellner src gnome org>]

commit 16914ddda3cd9c268bfe5aac3b582a11eca62aa3
Author: Florian Müllner <fmuellner gnome org>
Date:   Sat Feb 21 16:16:48 2015 +0100

    build: Use $(NULL) terminator for data files

 data/Makefile.am |   16 +++++++++++-----
 1 files changed, 11 insertions(+), 5 deletions(-)
---
diff --git a/data/Makefile.am b/data/Makefile.am
index bd2fac0..40078c9 100644
--- a/data/Makefile.am
+++ b/data/Makefile.am
@@ -1,4 +1,5 @@
 CLEANFILES =
+NULL =
 
 desktopdir=$(datadir)/applications
 desktop_DATA = gnome-shell.desktop gnome-shell-wayland.desktop  gnome-shell-extension-prefs.desktop
@@ -11,7 +12,8 @@ service_DATA = org.gnome.Shell.PortalHelper.service
 
 CLEANFILES += \
        org.gnome.Shell.PortalHelper.service \
-       org.gnome.Shell.PortalHelper.desktop
+       org.gnome.Shell.PortalHelper.desktop \
+       $(NULL)
 
 endif
 
@@ -33,7 +35,8 @@ introspection_DATA =                          \
        org.gnome.Shell.Screencast.xml          \
        org.gnome.Shell.Screenshot.xml          \
        org.gnome.ShellSearchProvider.xml       \
-       org.gnome.ShellSearchProvider2.xml
+       org.gnome.ShellSearchProvider2.xml      \
+       $(NULL)
 
 theme_sources =                                                \
        theme/HACKING                                           \
@@ -47,7 +50,8 @@ theme_sources =                                               \
        theme/gnome-shell-sass/_common.scss                     \
        theme/gnome-shell-sass/_drawing.scss                    \
        theme/gnome-shell-sass/_high-contrast-colors.scss       \
-       theme/gnome-shell-sass/gnome-shell-sass.doap
+       theme/gnome-shell-sass/gnome-shell-sass.doap            \
+       $(NULL)
 
 resource_files = $(shell $(GLIB_COMPILE_RESOURCES) --sourcedir=$(srcdir)/theme --generate-dependencies 
$(srcdir)/gnome-shell-theme.gresource.xml)
 gnome-shell-theme.gresource: gnome-shell-theme.gresource.xml $(resource_files)
@@ -100,7 +104,8 @@ EXTRA_DIST =                                                \
        org.gnome.Shell.PortalHelper.service.in         \
        org.gnome.shell.gschema.xml.in.in               \
        gnome-shell-theme.gresource.xml                 \
-       $(resource_files)
+       $(resource_files)                               \
+       $(NULL)
 
 CLEANFILES +=                                          \
        gnome-shell.desktop.in                          \
@@ -113,4 +118,5 @@ CLEANFILES +=                                               \
        gschemas.compiled                               \
        org.gnome.shell.gschema.valid                   \
        org.gnome.shell.gschema.xml.in                  \
-       gnome-shell-theme.gresource
+       gnome-shell-theme.gresource                     \
+       $(NULL)