Har file system doesn't deal with FS URIs with a host but no port

If you try to run an MR job with a Hadoop Archive as the input, but the URI you give it has no port specified (e.g. "hdfs://simon") the job will fail with an error like the following:

java.io.IOException: Incomplete HDFS URI, no host: hdfs://simon:-1/user/atm/input.har/input