cros_mark_all_as_stable: add tracking branch support

cros_mark_all_as_stable

 #!/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.
 
 # Wrapper scripts around cros_mark_as_stable that marks all packages as stable
 # that have CROS_WORKON_COMMIT that is different than the current HEAD commit
 # of the corresponding git repository.
 
 # 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"
 
 # Load common functions for workon scripts.
 . "$(dirname "$0")/lib/cros_workon_common.sh"
 
 get_default_board
 
 DEFINE_string board "${DEFAULT_BOARD}" \
   "The board to set package keywords for."
+DEFINE_string tracking_branch "origin" \
+  "Used with commit to specify branch to track against."
 
 FLAGS "$@" || exit 1
 eval set -- "${FLAGS_ARGV}"
 
 set -e
 
 BOARD_DIR=/build/"${FLAGS_board}"
 EQUERYCMD=equery-"${FLAGS_board}"
 EBUILDCMD=ebuild-"${FLAGS_board}"
 
@@ skipping 26 matching lines @@
     COMMIT_ID_LIST="${COMMIT_ID_LIST} ${head_commit}"
   elif [[ ${head_commit}  = ${egit_commit} ]]; then
     info "Commit id's match for ${package}"
   fi
 done
 
 info "Candidate package list ${PACKAGE_LIST}"
 info "With commit id list ${COMMIT_ID_LIST}"
 
 ./cros_mark_as_stable --board ${FLAGS_board} -p "${PACKAGE_LIST}" \
-  -i "${COMMIT_ID_LIST}" commit  || \
+  -i "${COMMIT_ID_LIST}" -t ${FLAGS_tracking_branch} commit  || \
     die "Could not mark all packages as stable"