This patch moves the logic for
- selection of connection to ping
- selection of connection to use
- selection of connection to prune
into own file and puts it behind a new interface called 'IceControllerInterface'.
BUG=webrtc:10647
Change-Id: I10228b3edd361d3200fa4a734d74a319560966c9
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/158205
Reviewed-by: Qingsi Wang <qingsi@webrtc.org>
Reviewed-by: Honghai Zhang <honghaiz@webrtc.org>
Commit-Queue: Jonas Oreland <jonaso@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#29850}
