Make chroot setup work better with NFS home dirs.

build/install-chroot.sh

 #!/bin/bash -e
 
 # Copyright (c) 2010 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 # This script installs Debian-derived distributions in a chroot environment.
 # It can for example be used to have an accurate 32bit build and test
 # environment when otherwise working on a 64bit machine.
 # N. B. it is unlikely that this script will ever work on anything other than a
@@ skipping 185 matching lines @@
 personality=linux$([ "${arch}" != 64bit ] && echo 32)
 script-config=script-${target}
 
 EOF
 
 # Set up a special directory that changes contents depending on the target
 # that is executing.
 sed '/^FSTAB=/s,/mount-defaults",/mount-'"${target}"'",'                       \
          /etc/schroot/script-defaults |
   sudo sh -c 'cat >/etc/schroot/script-'"${target}"
-sudo cp /etc/schroot/mount-defaults /etc/schroot/mount-"${target}"
+sed '\,^/home[/[:space:]],s/\([,[:space:]]\)bind[[:space:]]/\1rbind /' \
+  /etc/schroot/mount-defaults |
+  sudo sh -c 'cat > /etc/schroot/mount-'"${target}"
 echo "$HOME/chroot/.${target} $HOME/chroot none rw,bind 0 0" |
   sudo sh -c 'cat >>/etc/schroot/mount-'"${target}"
 mkdir -p "$HOME/chroot/.${target}"
 
 # Install a helper script to launch commands in the chroot
 sudo sh -c 'cat >/usr/local/bin/'"${target%bit}" <<EOF
 #!/bin/bash
 if [ \$# -eq 0 ]; then
   exec schroot -c ${target%bit} -p
 else
@@ skipping 99 matching lines @@
 
 Successfully installed ${distname} ${arch}
 
 You can run programs inside of the chroot by invoking the "${target%bit}"
 command.
 
 Your home directory is shared between the host and the chroot. But I configured
 $HOME/chroot to be private to the chroot environment. You can use it
 for files that need to differ between environments.
 EOF