void releaseBufferQuota(long size) {
    if (size < 0) {
      throw new IllegalArgumentException("size should not less than 0");
    }
    addTotalBufferUsed(-size);
  }
To release the buffer quota which acquired by
{@link ReplicationSourceManager#acquireBufferQuota}.
hbase-server/src/main/java/org/apache/hadoop/hbase/replication/regionserver/ReplicationSourceManager.java