This also swithces lifetime management of entries to using std::unique_ptr. Bug: chromium:1374310 Change-Id: I5a2c89e9b3bcf7bceec2a4e5347750540ee21e1f Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/279521 Commit-Queue: Tomas Gunnarsson <tommi@webrtc.org> Reviewed-by: Harald Alvestrand <hta@webrtc.org> Cr-Commit-Position: refs/heads/main@{#38432}