// start a region server here, so just manually create cphost
// and set it to region.
RegionCoprocessorHost host = new RegionCoprocessorHost(r, null, conf);
r.setCoprocessorHost(host);
host.load(implClass, Coprocessor.PRIORITY_USER, conf);
// we need to manually call pre- and postOpen here since the
// above load() is not the real case for CP loading. A CP is
// expected to be loaded by default from 1) configuration; or 2)
// HTableDescriptor. If it's loaded after HRegion initialized,
// the pre- and postOpen() won't be triggered automatically.