public void add(final PhaseDetails phaseDetails) {
            this.calls.addAndGet(phaseDetails.calls.get());
            this.affectedItemCount.addAndGet(phaseDetails.affectedItemCount.get());
            durationAdder.add(phaseDetails.durationAdder);
        }
Increment the call count by one, increment the count of items affected by the
phase by {@code count} and add the duration.

@param count    Number of items affected
@param duration The duration to add.
stroom-processor/stroom-processor-impl/src/main/java/stroom/processor/impl/ProgressMonitor.java