updated comment

Author: Alexandru Scvortov

src/com/rabbitmq/client/impl/ChannelN.java

@@ -171,7 +171,9 @@ public void releaseChannelNumber() {
 
     /**
      * Protected API - Filters the inbound command stream, processing
-     * Basic.Deliver, Basic.Return and Channel.Close specially.
+     * Basic.Deliver, Basic.Return and Channel.Close specially.  If
+     * we're in quiescing mode, all inbound commands are ignored,
+     * except for Channel.Close and Channel.CloseOk.
      */
     @Override public boolean processAsync(Command command) throws IOException
     {