This CL removes deprecated PeerConnectionFactory ctors as well as some deprecated comments and functions left from the PeerConnectionFactory.initialize work. Bug: webrtc:9158 Change-Id: I757f85b52cbfdbe15bf2570c394202b898892550 Reviewed-on: https://webrtc-review.googlesource.com/70400 Reviewed-by: Sami Kalliomäki <sakal@webrtc.org> Commit-Queue: Magnus Jedvert <magjed@webrtc.org> Cr-Commit-Position: refs/heads/master@{#23085}