MAPREDUCE-4846. Some JobQueueInfo methods are public in MR1 but protected in MR2. Contributed by Sandy Ryza.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1448597 13f79535-47bb-0310-9956-ffa450edef68
MAPREDUCE-5013. mapred.JobStatus compatibility: MR2 missing constructors from MR1. Contributed by Sandy Ryza.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1448602 13f79535-47bb-0310-9956-ffa450edef68
MAPREDUCE-4951. Container preemption interpreted as task failure. Contributed by Sandy Ryza.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1448615 13f79535-47bb-0310-9956-ffa450edef68
Merge remote branch 'origin/trunk' into trunk-gd
Merge remote branch 'origin/trunk-gd' into fb-HDFS-4310-trunk-gd