Add WritesQueryMetrics to EventQueryTransformer

[SethSmucker]

Update EventQueryTransformerSupport to implement WritesQueryMetrics so EventQueryTransformer has access to the methods.

Follows the structure of DocumentTransformerSupport implementing WritesQueryMetrics instead of implementing it directly into DocumentTransformer.

fixes #2605

[billoley]

I think the reason that EventQueryTransformer does not implement WritesQueryMetrics is that the logics using this transformer do not use the QueryIterator, do not track or return these metrics, and do not have a Document to call extractMetrics.

Recommend closing issue.