BUG=webrtc:7097 TEST=Set "ptime=120", try WebRTC calls over custom build Chromium with and without Opus 120ms. Try both Chromium w <-> Chromium w and Chromium w <-> Chromium w/o Review-Url: https://codereview.webrtc.org/2668633004 Cr-Commit-Position: refs/heads/master@{#16408}