Also improves ownership model by using std::unique_ptr in a couple of
places instead of raw pointers.
Bug: webrtc:8278
Change-Id: I0429ec3c416b5baa1ffa21dad71e0d64b004c446
Reviewed-on: https://webrtc-review.googlesource.com/25020
Commit-Queue: Magnus Jedvert <magjed@webrtc.org>
Reviewed-by: Sami Kalliomäki <sakal@webrtc.org>
Reviewed-by: Karl Wiberg <kwiberg@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#20863}