Ensure that PerformanceTiming context doesn't contain properties inherited from Object.prototype (closes #458)
Ensure that PerformanceTiming context doesn't contain properties inherited from Object.prototype (closes #458)

YieldifyLabs/snowplow-javascript-tracker,snowplow/snowplow-javascript-tracker,YieldifyLabs/snowplow-javascript-tracker,snowplow/snowplow-javascript-tracker,snowplow/snowplow-javascript-tracker,snowplow/snowplow-javascript-tracker,YieldifyLabs/snowplow-javascript-tracker