Preventing user CQDs from affecting metadata queries We now won't pass user CQDs to new CmpContext instance (CI) during embedded CI switch. This is to prevent metadata query plans being influenced by user CQDs unintentionally. Also, temporarily added a flag to retrieve the latest hbase snapshot info for user tables disrespect to whether we use the snapshots for scan or not. The CQD TRAF_TABLE_SNAPSHOT_SCAN will only affect the user query plan generations.
Reworked LP 1420826, Turning off nested_joins fails meta-data query compilation, by reverting the changes because when compiling the metadata queries, the default optimization level would be '3' and won't be affected by user setting anymore.
LP 1426479: Row mismatch between index/table cause init auth to fail. Fixed LP 1411355: User-level CQDs also seem to apply to metadata queries.