default void postBatchMutate(ObserverContext<? extends RegionCoprocessorEnvironment> c,
    MiniBatchOperationInProgress<Mutation> miniBatchOp) throws IOException {
  }
This will be called after applying a batch of Mutations on a region. The Mutations are added to
memstore and WAL. The difference of this one with
{@link #postPut(ObserverContext, Put, WALEdit)} and
{@link #postDelete(ObserverContext, Delete, WALEdit)} and
{@link #postIncrement(ObserverContext, Increment, Result, WALEdit)} and
{@link #postAppend(ObserverContext, Append, Result, WALEdit)} is this hook will be executed
before the mvcc transaction completion.
<p>
Note: Do not retain references to any Cells in Mutations beyond the life of this invocation. If
need a Cell reference for later use, copy the cell and use that.
@param c           the environment provided by the region server
@param miniBatchOp batch of Mutations applied to region. Coprocessors are discouraged from
                   manipulating its state.
hbase-server/src/main/java/org/apache/hadoop/hbase/coprocessor/RegionObserver.java