Merge "GetBootImageBuildProp returns None if file does not exist"

    RunAndCheckOutput(['toybox', 'cpio', '-F', abs_uncompressed_ramdisk, '-i'],

               cwd=extracted_ramdisk)

    prop_file = None

    for search_path in RAMDISK_BUILD_PROP_REL_PATHS:

      prop_file = os.path.join(extracted_ramdisk, search_path)

      if os.path.isfile(prop_file):

        break

        return prop_file

      logger.warning('Unable to get boot image timestamp: no %s in ramdisk', search_path)

    return prop_file

    return None

  except ExternalError as e:

    logger.warning('Unable to get boot image build props: %s', e)