Returning from registerWithDispatcher(..) if dispatcher is null (INT-164).

spring-integration-core/src/main/java/org/springframework/integration/bus/MessageBus.java

@@ -368,6 +368,7 @@ public class MessageBus implements ChannelRegistry, EndpointRegistry, Applicatio
 			if (logger.isWarnEnabled()) {
 				logger.warn("no dispatcher available for channel '" + channel.getName() + "', be sure to register the channel");
 			}
+			return;
 		}
 		dispatcher.addHandler(handler, schedule);
 		if (this.isRunning() && !dispatcher.isRunning()) {