791adafa09
This adds the necessary properties and callback to the Send Queue to support the bufferedAmount & bufferedAmountLowThreshold properties and the bufferedamountlow event in RTCDataChannel. The public API changes and socket support comes in a follow-up CL. Bug: webrtc:12794 Change-Id: I12a16f44f775da3711f3aa52a68a0bf24f70d2f8 Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/219690 Reviewed-by: Harald Alvestrand <hta@webrtc.org> Commit-Queue: Victor Boivie <boivie@webrtc.org> Cr-Commit-Position: refs/heads/master@{#34142}