[FOR TESTING] Add consumer.degrade()

[ibc]

Details

In Consumer.ts:

/**
 * Degrade RTP transmission.
 * - durationMs: Duration that the degradation will take.
 * - maxDelayMs: Max delay (in ms) to be applied to each packet.
 * - delayPercent: Only apply delay to this percent of the packets.
 * - lossPercent: Generate packet loss by given percent value.
 *
 * @remarks
 * - Only implemented in `SimpleConsumer`.
 * - After `durationMs`, or if `consumer.degrade()` is called again with
 *   `durationMs: 0`, then degradation is immediately stopped and all delayed
 *   buffered packets are immediately sent (all together).
 *
 * @throws
 * - If called on a non `SimpleConsumer` (due to method not implemented).
 *
 * @example
 * ```ts
 * consumer.degrade({
 *   durationMs: 10000
 *   maxDelayMs: 3000,
 *   delayPercent: 20,
 *   lossPercent: 0,
 * });
 * ```
 */
degrade({
	durationMs,
	maxDelayMs,
	delayPercent,
	lossPercent,
}: {
	durationMs?: number;
	maxDelayMs?: number;
	delayPercent?: number;
	lossPercent?: number;
}): Promise<void>;

Usage example in the mediasoup-demo

--- a/server/lib/Room.js
+++ b/server/lib/Room.js
@@ -1752,6 +1752,17 @@ class Room extends EventEmitter
 								paused          : true,
 								ignoreDtx       : true
 							});
+
+						// TODO: Testing degradation.
+						if (consumer.kind === 'video')
+						{
+							consumer.degrade({
+								durationMs: 5000,
+								maxDelayMs: 3000,
+								delayPercent: 50,
+								lossPercent: 0,
+							});
+						}
 					}
 					catch (error)
 					{