HDFS-4661. A few little code cleanups of some HDFS-347-related code. Contributed by Colin Patrick McCabe.


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1483210 13f79535-47bb-0310-9956-ffa450edef68
HDFS-4698. Provide client-side metrics for remote reads, local reads, and short-circuit reads. Contributed by Colin Patrick McCabe.


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1483211 13f79535-47bb-0310-9956-ffa450edef68