Do not close InputStream from InputStreamSource

Test: I28f82285c0341aff7192eb0157e0de4b97cda577

This is called by public methods that pass along an InputStream. As
such, it is possible that the client was planning to continue reading
from the InputStream, so do not close it.

Change-Id: Iaa53c44d578c1311315616c8fd931bed40290a92