Separated out EventPlayer from pqViewStreamingBehavior

The pqViewStreamingBehavior contains and instantiates its own event
player to play back its recorded event. The new QtTesting flow does
not support this. The players have to be registered first before
recorded event can be dispatched to the player. So the internal
event class is moved out to be a new class and registerd on its own.

Change-Id: I8c4b48a492a0088a6dcdf8de82313bee8185ec54
Merge topic 'update-qttesting' into next

3f6e30bb Separated out EventPlayer from pqViewStreamingBehavior