public boolean waitMetaAssigned(Procedure<?> proc, RegionInfo regionInfo) {
    return getMetaAssignEvent(getMetaForRegion(regionInfo)).suspendIfNotReady(proc);
  }
Notice that this event does not mean the AM has already finished region state rebuilding. See
the comment of {@link #isMetaAssigned()} for more details.
@see #isMetaAssigned()
hbase-server/src/main/java/org/apache/hadoop/hbase/master/assignment/AssignmentManager.java