Affects Version/s: 0.92.0
Fix Version/s: None
Each call for HTable.getStartEndKeys will read meta table.
in the case of client side multi-threaded concurrency statistics,
we must call HTable.coprocessorExec== > getStartKeysInRange ==> getStartEndKeys,
resulting in the need to always scan the meta table.
This is not necessary,
we can implement the HConnectionManager.HConnectionImplementation.locateRegions(byte tableName) method,
then, get the StartKeys and EndKeys from the cachedRegionLocations of HConnectionImplementation.
Combined with https://issues.apache.org/jira/browse/HBASE-5491, can improve the performance of statistical