http://codereview.chromium.org/2742009/diff/1/2
File chromeos-postinst (right):
http://codereview.chromium.org/2742009/diff/1/2#newcode17
chromeos-postinst:17: ROOT_DEV=echo "${INSTALL_DEV}" | sed
's/p*[0-9]*//g'
Can you source /usr/sbin/chromeos-common.sh and use
ROOT_DEV=$(get_block_dev_from_partition_dev ${INSTALL_DEV}) instead?
That function already solves this problem.