This starts to fix the scripts so that they load from /usr/lib/crosutils

clean_loopback_devices

+#!/bin/sh
 # Copyright (c) 2010 The Chromium OS Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 #
 # Force cleans loopback devices from within your chroot environment.  This
 # script is to help mitigate losing loopback devices on build_images
 # failures.  This script only affects mountpoints and loopback devices
 # that were created within this chroot.
 
-# Load common constants.  This should be the first executable line.
-# The path to common.sh should be relative to your script's location.
-. "$(dirname "$0")/common.sh"
+# --- BEGIN COMMON.SH BOILERPLATE ---
+# Load common CrOS utilities.  Inside the chroot this file is installed in
+# /usr/lib/crosutils.  Outside the chroot we find it relative to the script's
+# location.
+find_common_sh() {
+  local common_paths=(/usr/lib/crosutils $(dirname "$(readlink -f "$0")"))
+  local path
+
+  SCRIPT_ROOT=
+  for path in "${common_paths[@]}"; do
+    if [ -r "${path}/common.sh" ]; then
+      SCRIPT_ROOT=${path}
+      break
+    fi
+  done
+}
+
+find_common_sh
+. "${SCRIPT_ROOT}/common.sh" || (echo "Unable to load common.sh" && exit 1)
+# --- END COMMON.SH BOILERPLATE ---
 
 # Script must be run inside the chroot.
 assert_inside_chroot
 
 DEFINE_string output_root "$DEFAULT_BUILD_ROOT/images" \
   "Directory in which to place image result directories (named by version)"
 DEFINE_string board "$DEFAULT_BOARD" \
   "The board to build an image for."
 
 OUTPUT_DIR="${FLAGS_output_root}/${FLAGS_board}"
 
 echo "This will unmount any directory under $OUTPUT_DIR:"
 read -p "Are you sure (y/N)? " SURE
 SURE="${SURE:0:1}" # Get just the first character
-if [ "${SURE}" != "y" ]
-then
+if [ "${SURE}" != "y" ]; then
   echo "Ok, better safe than sorry."
   exit 1
 fi
 
 sudo umount "$OUTPUT_DIR"/*/* 2> /dev/null
 sudo losetup -d /dev/loop* 2> /dev/null