public boolean waitRegion(final Procedure<?> procedure, final RegionInfo regionInfo) {
    return waitRegions(procedure, regionInfo.getTable(), regionInfo);
  }
Suspend the procedure if the specified region is already locked.
@param procedure  the procedure trying to acquire the lock on the region
@param regionInfo the region we are trying to lock
@return true if the procedure has to wait for the regions to be available
hbase-server/src/main/java/org/apache/hadoop/hbase/master/procedure/MasterProcedureScheduler.java