CappedOperation does not trigger on first time event

Previously, a CappedOperation was triggered the first event regardless of
which triggered were specified. This was unexpected and counter intuitive,
especially for cases (where it is most used) where a CappedOperation was
added as a time-based logger and a log statement was expected to be
printed after the specified threshold, it would log immediately as well.
Merge pull request #3227 from tinwelint/1.9-capped-ops-no-first

[1.9] CappedOperation does not trigger on first time event