[PATCH] gdk-pixbuf: Avoid rebuild failures

[Richard Purdie <richard.purdie@linuxfoundation.org>]

If gdkpixbuf-native rebuilds and there are stale (broken) modules lying around,
it can fail to run the postinst. E.g. svg links to harfbuzz and if harfbuzz is
removed from the sysroot but the svg loader isn't, we get a symbol linking issue.

The reproducer is along the lines of build gdk-pixbuf-native along
with harfbuzz-native and librsvg-native, then make a small change to the
gdk-pixbuf recipe that would cause it to rebuild, clean harfbuzz-native
and then build gdk-pixbuf.

To fix this, when we install gdk-pixbuf, we wipe out any previous loaders.
The idea is that gdk would always come first and anything else installing
itself will come later and rerun the postinst if needed. We can therefore
just remove any other loaders.

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

diff --git a/meta/recipes-gnome/gdk-pixbuf/gdk-pixbuf_2.30.8.bb b/meta/recipes-gnome/gdk-pixbuf/gdk-pixbuf_2.30.8.bb
index bdf173a..35bb192 100644
--- a/meta/recipes-gnome/gdk-pixbuf/gdk-pixbuf_2.30.8.bb
+++ b/meta/recipes-gnome/gdk-pixbuf/gdk-pixbuf_2.30.8.bb
@@ -94,3 +94,12 @@ do_install_append_class-native() {
 		GDK_PIXBUF_MODULEDIR=${STAGING_LIBDIR_NATIVE}/gdk-pixbuf-2.0/${LIBV}/loaders
 }
 BBCLASSEXTEND = "native"
+
+SSTATEPREINSTFUNCS_append_class-native = " gdkpixbuf_sstate_preinst"
+SYSROOT_PREPROCESS_FUNCS_append_class-native = " gdkpixbuf_sstate_preinst"
+
+gdkpixbuf_sstate_preinst() {
+	if [ "${BB_CURRENTTASK}" = "populate_sysroot" -o "${BB_CURRENTTASK}" = "populate_sysroot_setscene" ]; then
+		rm -rf ${STAGING_LIBDIR_NATIVE}/gdk-pixbuf-2.0/${LIBV}/*
+	fi
+}