Adds a function to PeerConnectionIntegrationBaseTest to stop and destroy
the caller and callee objects. This should take care of dangling pointers.
Before this change, the affected test would crash randomly - typically
detected within a few minutes of a gtest-repeat=-1 run.
After this change, it has not crashed in 15 minutes of running.
Bug: webrtc:12592
Change-Id: I9980f8974015bf2b2104fcb83c2ca0d677d03c3e
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/264555
Reviewed-by: Henrik Boström <hbos@webrtc.org>
Commit-Queue: Harald Alvestrand <hta@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#37096}
4f7486ab3b