When an error occurs, the callback needs to be invoked or the signaling thread may block indefinitely waiting for it. Bug: webrtc:15871 Change-Id: Ib73382aff07b3632794300985223c70c24f554f4 Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/342901 Reviewed-by: Florent Castelli <orphis@webrtc.org> Reviewed-by: Ilya Nikolaevskiy <ilnik@webrtc.org> Commit-Queue: Ilya Nikolaevskiy <ilnik@webrtc.org> Cr-Commit-Position: refs/heads/main@{#41904}