1)fixed read-lock escalation bug by mimicking SIX mode with allowing S and IX coexist in dataset-level and 2) released all previousely acquired locks when escalation completed

git-svn-id: https://asterixdb.googlecode.com/svn/branches/asterix_lsm_stabilization@1472 eaa15691-b419-025a-1212-ee371bd00084
2 files changed