The `goog.debug.Trace_.Event_` Class

`.toString()`

returns {string}: A string describing the tracer event.

`.toTraceString(startTime, prevTime, indent)`

Returns a formatted string for the event.

startTime {number}: The start time of the trace to generate relative times.
prevTime {number}: The completion time of the previous event or -1.
indent {string}: Extra indent for the message if there was no previous event.
returns {string}: The formatted tracer string.

`.type` {`string`|`null`|`undefined`}