Update prebuilt.py call to use the _proper_ variable for finding the build root.

archive_build.sh

 #!/bin/bash
 
 # 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.
 
 # Script to archive build results.  Used by the buildbots.
 
 # Load common constants.  This should be the first executable line.
 # The path to common.sh should be relative to your script's location.
@@ skipping 255 matching lines @@
     "${LAST_CHANGE}/${HWQUAL_NAME}.tar.bz2"
 fi
 
 
 if [ $FLAGS_prebuilt_upload -eq $FLAGS_TRUE ]
 then
   # Construct prebuilt upload command.
   # This will upload prebuilt packages to Google Storage.
   prebuilt_cmd="${SCRIPTS_DIR}/prebuilt.py"
   prebuilt_cmd="$prebuilt_cmd -u gs://chromeos-prebuilt --git-sync -V master"
-  prebuilt_cmd="$prebuilt_cmd -p $(readlink -f ../../../../build/chromiumos)"
-  prebuilt_cmd="$prebuilt_cmd -b ${FLAGS_board}"
+  prebuilt_cmd="$prebuilt_cmd -p ${GCLIENT_ROOT} -b ${FLAGS_board}"
 
   if [ "${FLAGS_BOARD}" == "x86-generic" ]
   then
     prebuilt_cmd="$prebuilt_cmd --sync-host"
   fi
 
   echo "Running $prebuilt_cmd"
   $prebuilt_cmd
 fi
 
@@ skipping 25 matching lines @@
 if [ $FLAGS_keep_max -gt 0 ]
 then
   echo "Deleting old builds (all but the newest ${FLAGS_keep_max})..."
   cd "$FLAGS_to"
   # +2 because line numbers start at 1 and need to skip LATEST file
   rm -rf `ls -t1 | tail --lines=+$(($FLAGS_keep_max + 2))`
   cd -
 fi
 
 echo "Done."