MESSAGE_QUEUE_POST_PROCESS event still gets dispatched after MESSAGE_OUTGOING_POST_PROCESS and MESSAGE_POST_PROCESS when skip_queue is true

Problem Statement

The SmsEvents::MESSAGE_QUEUE_POST_PROCESS event will still get dispatched after SmsEvents::MESSAGE_OUTGOING_POST_PROCESS and SmsEvents::MESSAGE_POST_PROCESS are dispatched if the gateway happens to have skip_queue TRUE.

Even though it is documented that skip_queue is not recommended in production, this is still a WTF for development and testing where the post process event handlers would behave funny in a test (for instance).

Proposed resolution

Filter out messages that have passed through a gateway with skip_queue on before passing them through the MESSAGE_QUEUE_POST_PROCESS event dispatch.