A couple crashes have been reported in Chromium due to us dereferencing |result.frame| which can be a nullptr. This bug tracks the addition of new test cases which will help us avoid issues like this in the future: https://bugs.chromium.org/p/webrtc/issues/detail?id=12682 Bug: chromium:1199257 Change-Id: I720dd6ceb38938dc392f0924acf2cac287bfcffc Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/215340 Reviewed-by: Jamie Walch <jamiewalch@chromium.org> Commit-Queue: Austin Orion <auorion@microsoft.com> Cr-Commit-Position: refs/heads/master@{#33746}