factory_test_init: prevent info messages displayed as "ERROR"

factory.conf

 # Copyright (c) 2011 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.
 
 description   "Chrome OS factory startup stub"
 author        "chromium-os-dev@chromium.org"
 
 start on stopped udev-addon
 stop on starting halt or starting reboot
 
@@ skipping 11 matching lines @@
   fi
   FACTORY_LOG_FILE=/var/log/factory.log
   CONSOLE_LOG_FILE=/var/log/factory_console.log
   # Factory log will be uploaded so we must always preserve previous results.
   # Console log is just for UI to display, no need to be saved across sessions;
   # however in order to support writing by multiple processes, the file must be
   # opened in "append" mode. So we must first delete it then use >> to append.
   rm -f "$CONSOLE_LOG_FILE"
   ./bin/autotest -t factory $OPT control 2>&1 |
     tee -a "$FACTORY_LOG_FILE" |
-    grep --line-buffer "FACTORY" >>"$CONSOLE_LOG_FILE"
+    grep --line-buffer "FACTORY" |
+    sed -u 's/^\([0-9:]*\) ERROR| FACTORY: /\1 | /' >>"$CONSOLE_LOG_FILE"
 end script
 
 pre-stop script
   pkill python
   pkill X
 end script