Include timestamp in ScriptEvaluateResult

[juliandescottes]

@nchevobbe was mentioning a typical DevTools console issue related to ordering of messages.

We already support a timeStamp property for log.entryAdded events, however in all Console-like UIs which allow to also execute script, log messages are displayed together with evaluation results . For a simple example consider evaluating console.log(1); "hi"

The 1 is a log message (ie log.entryAdded in BiDi), whereas the "hi" is the result of the evaluation (would be a ScriptEvaluateResult in BiDi). If we want clients to be able to build such UIs, it would be great if they could have consistent timeStamp information for both log events but also for ScriptEvaluateResult.

Would it make sense to extend the ScriptEvaluateResult to add a timeStamp property?
If awaitPromise is false it would be set when the script or function declaration is executed.
If awaitPromise is true it would be set when the promise resolves.

[juliandescottes]

One additional comment, for really accurate message ordering it might be necessary to go down to microsecond precision. Right now our timestamps are in milliseconds (https://tc39.es/ecma262/#sec-time-values-and-time-range). Otherwise clients might have to take arbitrary decisions on the ordering of messages which share the timestamp