public void wakeMetaLoadedEvent() {
    metaLoadEvent.wake(getProcedureScheduler());
    assert isMetaLoaded() : "expected meta to be loaded";
  }
This method will be called in master initialization method after calling
{@link #processOfflineRegions()}, as in processOfflineRegions we will generate assign
procedures for offline regions, which may be conflict with creating table.
<p/>
This is a bit dirty, should be reconsidered after we decide whether to keep the
{@link #processOfflineRegions()} method.
hbase-server/src/main/java/org/apache/hadoop/hbase/master/assignment/AssignmentManager.java