Fix signing failure for split APKs

        "Failed to obtain minSdkVersion for {}: aapt2 return code {}:\n{}\n{}".format(

            apk_name, proc.returncode, stdoutdata, stderrdata))

  is_split_apk = False

  for line in stdoutdata.split("\n"):

    # See b/353837347 , split APKs do not have sdk version defined,

    # so we default to 21 as split APKs are only supported since SDK

    # 21.

    if (re.search(r"split=[\"'].*[\"']", line)):

      is_split_apk = True

    # Due to ag/24161708, looking for lines such as minSdkVersion:'23',minSdkVersion:'M'

    # or sdkVersion:'23', sdkVersion:'M'.

    m = re.match(r'(?:minSdkVersion|sdkVersion):\'([^\']*)\'', line)

    if m:

      return m.group(1)

  if is_split_apk:

    logger.info("%s is a split APK, it does not have minimum SDK version"

                " defined. Defaulting to 21 because split APK isn't supported"

                " before that.", apk_name)

    return 21

  raise ExternalError("No minSdkVersion returned by aapt2 for apk: {}".format(apk_name))