GitLab

Remove WebRTC-SystemUDPSendSocketSize which is long expired and not useful anymore.

Also removing an unused include from ipc_socket_factory.cc which I missed in
https://chromium-review.googlesource.com/c/chromium/src/+/854947

Bug: 799180
Change-Id: Iaa733fff48e7334ceafb3b212866c83822f369d1
Reviewed-on: https://chromium-review.googlesource.com/857884Reviewed-by: Sergey Ulanov <sergeyu@chromium.org>
Commit-Queue: Gayane Petrosyan <gayane@chromium.org>
Cr-Commit-Position: refs/heads/master@{#533006}