As long as there is no RegionServerServices for a master local region, we need implement log
roller logic by our own.
We can reuse most of the code for normal wal roller, the only difference is that there is only
one region, so in scheduleFlush(String, List) method we can just schedule flush
for the master local region.
Nested Class Summary
Nested classes/interfaces inherited from class org.apache.hadoop.hbase.wal.AbstractWALRoller