When the assertion triggers, manual action is likely needed. This CL changes the error message to make it more clear. No-Try: True Bug: webrtc:11369 Change-Id: I7d8b04deef7638e715b12e6dceeee9cc2ce2cc66 Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/168761 Commit-Queue: Mirko Bonadei <mbonadei@webrtc.org> Reviewed-by: Patrik Höglund <phoglund@webrtc.org> Cr-Commit-Position: refs/heads/master@{#30553}