Make more build scripts barf when run as root.

src/scripts/build_tests.sh

 #!/bin/bash
 
 # Copyright (c) 2009 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.
 
 # 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"
 
+assert_inside_chroot
+assert_not_root_user
+
 # Flags
 
 # Parse command line
 FLAGS "$@" || exit 1
 eval set -- "${FLAGS_ARGV}"
 
 # Die on error; print commands
 set -e
 
 PLATFORM_DIR="$SRC_ROOT/platform"
 PLATFORM_DIRS="pam_google window_manager cryptohome"
 
 # Build tests
 for i in $PLATFORM_DIRS
 do
   echo "building $PLATFORM_DIR/$i"
   cd "$PLATFORM_DIR/$i"
   ./make_tests.sh
   cd -
 done
 
 echo "All tests built."