JMS Resource adapater should throw an exception if a Connection Consumer is not created successfully

The protected void setupConsumer() method in JmsServerSessionPool.java is using the optional JMS method createConnectionConsumer.
However it doesn't check for the return value properly and throw an exception if it's null.

Some JMS providers do not implement this method, hence the return value could be null. - (As per the JMS spec, null is a valid return value)