Add build flag for iterative vm testing.

bin/cros_run_vm_test

 #!/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.
 #
 # Runs a given test case under a VM.
 
 # --- BEGIN COMMON.SH BOILERPLATE ---
 # Load common CrOS utilities.  Inside the chroot this file is installed in
@@ skipping 18 matching lines @@
 
 . "${SCRIPT_ROOT}/lib/cros_vm_lib.sh" || die "Unable to load cros_vm_lib.sh"
 . "${SCRIPT_ROOT}/lib/cros_vm_constants.sh" || \
   die "Unable to load cros_vm_constants.sh"
 
 MAX_RETRIES=3
 
 get_default_board
 
 DEFINE_string board "$DEFAULT_BOARD" \
-    "The board for which you built autotest." b
+    "The board for which you built autotest."
+DEFINE_boolean build ${FLAGS_FALSE} "Build tets while running" b
 DEFINE_string image_path "" "Full path of the VM image"
 DEFINE_string results_dir_root "" "alternate root results directory"
 DEFINE_string test_case "" "Name of the test case to run"
 DEFINE_boolean use_emerged ${FLAGS_FALSE} \
     "Force use of emerged autotest packages"
 DEFINE_string verify_chrome_version "" \
     "Verify that this chrome version matches that on vm."
 
 set -e
 
@@ skipping 47 matching lines @@
     chrome_version_on_vm=$("${SCRIPTS_DIR}/bin/cros_get_chrome_version" \
         --remote=127.0.0.1 \
         --ssh_port=${FLAGS_ssh_port})
     [[ ${chrome_version_on_vm} == ${FLAGS_verify_chrome_version} ]] || \
         warn "CHROME_VERSION is no longer set.This check will be removed"
   else
     warn "${FLAGS_verify_chrome_version} is not a valid Chrome version"
   fi
 fi
 
+# Set the build flag for run_remote_tests.
+BUILD_FLAG=""
+[ ${FLAGS_build}-eq ${FLAGS_true} ] && BUILD_FLAG="--build"
+
 "${SCRIPTS_DIR}/run_remote_tests.sh" \
     --board=${FLAGS_board} \
+    ${BUILD_FLAG} \
     --ssh_port=${FLAGS_ssh_port} \
     --remote=127.0.0.1 \
     --results_dir_root="${FLAGS_results_dir_root}" \
     ${USE_EMERGED} \
     "${tests[@]}"