Remove explicit set of UPOWER_CONF_FILE_NAME in up-self-test.c;
instead the harness should set it.  In Guix we set it explicitly; the
right thing is to use AM_TEST_ENVIRONMENT and regenerate the
makefiles, but we can't regenerate because current autotools carp on
some things, so we patch the Makefile.in instead.

Also fix to not try to create /var/lib/upower if /var isn't writable.

Patch by Andy Wingo <wingo@igalia.com>

--- upower-0.99.2.orig/src/Makefile.in	2014-12-18 10:32:01.000000000 +0100
+++ upower-0.99.2/src/Makefile.in	2015-04-04 19:49:28.020843678 +0200
@@ -780,6 +780,7 @@
 
 @UP_BUILD_TESTS_TRUE@up_self_test_CFLAGS = $(AM_CFLAGS) $(WARNINGFLAGS_C)
 @UP_BUILD_TESTS_TRUE@TESTS_ENVIRONMENT = $(DBUS_LAUNCH)
+@UP_BUILD_TESTS_TRUE@AM_TESTS_ENVIRONMENT = UPOWER_CONF_FILE_NAME=$(top_srcdir)/etc/UPower.conf
 dbusservicedir = $(datadir)/dbus-1/system-services
 dbusservice_in_files = org.freedesktop.UPower.service.in
 dbusservice_DATA = $(dbusservice_in_files:.service.in=.service)
@@ -1789,7 +1790,7 @@
 @HAVE_SYSTEMDSYSTEMUNITDIR_TRUE@	@sed -e "s|\@libexecdir\@|$(libexecdir)|" $< > $@
 
 install-data-hook:
-	if test -w $(DESTDIR)$(prefix)/; then \
+	if test -w $(DESTDIR)$(localstatedir)/; then \
 		mkdir -p $(DESTDIR)$(historydir); \
 	fi
 
--- upower-0.99.2.orig/src/up-self-test.c	2014-07-17 09:46:15.000000000 +0200
+++ upower-0.99.2/src/up-self-test.c	2015-04-04 18:43:04.952741927 +0200
@@ -295,12 +295,6 @@
 #endif
 	g_test_init (&argc, &argv, NULL);
 
-	/* make check, vs. make distcheck */
-	if (g_file_test ("../etc/UPower.conf", G_FILE_TEST_EXISTS))
-		g_setenv ("UPOWER_CONF_FILE_NAME", "../etc/UPower.conf", TRUE);
-	else
-		g_setenv ("UPOWER_CONF_FILE_NAME", "../../etc/UPower.conf", TRUE);
-
 	/* tests go here */
 	g_test_add_func ("/power/backend", up_test_backend_func);
 	g_test_add_func ("/power/device", up_test_device_func);
