HBASE-9514 Prevent region from assigning before log splitting is done

git-svn-id: https://svn.apache.org/repos/asf/hbase/branches/0.96@1528231 13f79535-47bb-0310-9956-ffa450edef68
HBASE-9514 Prevent region from assigning before log splitting is done - ADDENDUM

git-svn-id: https://svn.apache.org/repos/asf/hbase/branches/0.96@1528247 13f79535-47bb-0310-9956-ffa450edef68