divert grub-install on snappy images during rootfs build

debian/changelog

@@ -1,3 +1,9 @@
+livecd-rootfs (2.347) UNRELEASED; urgency=medium
+
+  * divert grub-install on snappy images during rootfs build
+
+ -- Oliver Grawert <ogra@ubuntu.com>  Fri, 09 Oct 2015 12:44:04 +0200
+
 livecd-rootfs (2.346) wily; urgency=medium
 
   * merge lp:~sil2100/livecd-rootfs/remove_apt_lists to drop cruft from

live-build/ubuntu-core/hooks/01-divert-grub-install.chroot_early

@@ -0,0 +1,13 @@
+#!/bin/sh -ex
+
+dpkg-divert --quiet --add \
+        --divert /usr/sbin/grub-install.REAL --rename \
+        /usr/sbin/grub-install
+
+cat > /usr/sbin/grub-install <<'EOF'
+#! /bin/sh
+echo "grub-install: diverted by livecd-rootfs (will be called later)" >&2
+exit 0
+EOF
+
+chmod +x /usr/sbin/grub-install

live-build/ubuntu-core/hooks/99-undivert-grub-install.chroot

@@ -0,0 +1,4 @@
+#! /bin/sh -ex
+
+rm -f /usr/sbin/grub-install
+dpkg-divert --quiet --remove --rename /usr/sbin/grub-install