Log SendSideCongestionController experiment
Log SendSideCongestionController experiment

The SendSideCongestionController version is toggled by an experiment in
RtpTransportControllerSend. This CL adds a log statement of which
version is used, to make debugging easier.

Bug: webrtc:8415
Change-Id: I6201cf5f03e097cc07c6ae120dcff075c046c414
Reviewed-on: https://webrtc-review.googlesource.com/69808
Commit-Queue: Sebastian Jansson <c24d1bc144eb7c11e553f59153fa17dba85ca83e@webrtc.org>
Reviewed-by: Niels Moller <0057859e47d61d90529d0f66d9ef692cefedb46a@webrtc.org>
Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#22858}
ShiftMediaProject/libilbc,TimothyGu/libilbc,TimothyGu/libilbc,ShiftMediaProject/libilbc,TimothyGu/libilbc,ShiftMediaProject/libilbc,TimothyGu/libilbc,ShiftMediaProject/libilbc,TimothyGu/libilbc,ShiftMediaProject/libilbc