public synchronized void setSnapshotHandlerForTesting(final TableName tableName,
    final SnapshotSentinel handler) {
    if (handler != null) {
      this.snapshotHandlers.put(tableName, handler);
    } else {
      this.snapshotHandlers.remove(tableName);
    }
  }
Set the handler for the current snapshot
<p>
Exposed for TESTING
@param handler handler the master should use TODO get rid of this if possible, repackaging,
               modify tests.
hbase-server/src/main/java/org/apache/hadoop/hbase/master/snapshot/SnapshotManager.java