HBASE-9184 Ignore zk assign event if region is not known in transition

git-svn-id: https://svn.apache.org/repos/asf/hbase/trunk@1513294 13f79535-47bb-0310-9956-ffa450edef68
HBASE-9146 TestHTablePool hangs when run as part of runMediumTests profile (Rajesh Venkatachalam)

git-svn-id: https://svn.apache.org/repos/asf/hbase/trunk@1513302 13f79535-47bb-0310-9956-ffa450edef68
HBASE-9197 TestAdmin#testShouldCloseTheRegionBasedOnTheEncodedRegionName shuts down the namespaces table and never starts it up again

git-svn-id: https://svn.apache.org/repos/asf/hbase/trunk@1513306 13f79535-47bb-0310-9956-ffa450edef68
Merge remote branch 'origin/trunk' into trunk-gd
Merge remote branch 'origin/trunk-gd' into fb-HBASE-8559-trunk-gd