Add support for custom startInteraction start input events

[pyricau]

No description provided.

[elizrus]

Do we want papa responsible for inputData accounting? In the integration on register we'd probably carry any data through InteractionEvent

[pyricau]

So yes, the general idea is that we have the custom timestamp passed in as a property of the sent event, and then in the interaction rule client, we read that and pass it in to startInteraction. In that specific case, we don't need inputData at all (so now that I think of it is should probs be inputData: Any? = null).

The inputData field is here for the receiving end, where we get the InteractionResult and pull out the input details

E.g. look for interactionInput usages here (Square internal link): https://github.com/squareup/android-register/blob/master/common/ui-latency/impl/src/main/java/com/squareup/uilatency/InteractionLatencyAnalytics.kt

ui_latency_trigger_frames = result.interactionInput?.framesSinceDelivery?.toLong()?: -1,

=> this needs access to the DeliveredInput which in this PR we shove inside InteractionStartInput.inputData

  private val InteractionResultData<InteractionEvent>.interactionType: String
    get() = interactionInput?.let {
      when (val inputEvent = it.event) {
        is MotionEvent -> "tap"
        is KeyEvent -> {
          "key ${inputEvent.name}"
        }

        else -> error("Unexpected input event type $inputEvent")
      }
    } ?: "unknown"

=> here we're mostly looking for a string description of the event.

  private val InteractionResultData<InteractionEvent>.triggerDuration: Duration?
    get() {
      val firstEvent = sentEvents.first()
      val triggerUptime = interactionInput?.eventUptime
      return triggerUptime?.let { firstEvent.uptime - it }
    }

=> This one only uses eventUptime which is carried over as inputUptime, so that one doesn't need inputData.

I'm thinking maybe I should turn InteractionStartInput into an interface implemented by DeliveredInput, that can be implemented by our custom things, and then I can remove inputData from it and just have inputUptime

[pyricau]

done!