There is only one NTP clock now.
Bug: webrtc:11327
Change-Id: I8c2808cf665f92bd251d68e32062beeffabb0f43
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/214132
Commit-Queue: Paul Hallak <phallak@google.com>
Reviewed-by: Danil Chapovalov <danilchap@webrtc.org>
Reviewed-by: Minyue Li <minyue@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#33657}