MAPREDUCE-5028. Fixed a bug in MapTask that was causing mappers to fail when a large value of io.sort.mb is set. Contributed by Karthik Kambatla.


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1576170 13f79535-47bb-0310-9956-ffa450edef68