Comment 4 for bug 1720217

As part of verifying this SRU I had to change the test case to point to current lp:~ubuntu-core-dev/livecd-rootfs/livecd-rootfs-xenial, not because of any bug in the live-build SRU, but because the previously referenced branch would not reliably trigger the original bug against xenial (due to undefined ordering of initramfs-tools configuration).

These livecd-rootfs branches also had already added a versioned dependency on the xenial-proposed version of live-build, so the test case cannot be completed as written. Modifying the livecd-rootfs package to drop this versioned dependency is required; otherwise livecd-rootfs is unpacked but not configured, which prevents other packages to be successfully installed as part of the build by livecd-rootfs itself using apt.

Once livecd-rootfs is correctly installed with the relaxed dependency, the original failure is reproducible as expected; and upgrading to the xenial-proposed version of live-build resolves it.