This method is called after an event has been played to prepare for the next event.
@param {Object} eventDescriptor The descriptor of the event just played.
function (eventDescriptor) {
        var me = this,
            index = ++me.queueIndex;

        // keyframe events are inserted after a keyFrameEvent is played.
        if (me.keyFrameEvents[eventDescriptor.type]) {
            Ext.Array.insert(me.eventQueue, index, [
                { keyframe: true, ts: eventDescriptor.ts }
            ]);
        }
    }