Revert "Reland "Remove GICE (gone forever!) and PORTALLOCATOR_ENABLE_SHARED_UFRAG (enabled forever)." becauese remoting code is using dead constants and breaks the FYI bots.""

This reverts commit 081f34b564e1a26ffbbe9515eba1fef7c736fdde.

Original code review see
https://codereview.webrtc.org/1291363005

The revert is due to a suspicion of "Reland "Remove GICE..." being the cause of failure on Linux memcheck, see
https://build.chromium.org/p/client.webrtc/builders/Linux%20Memcheck/builds/4137

TBR=pthatcher@webrtc.org,

BUG=

Review URL: https://codereview.webrtc.org/1308753003 .

Cr-Commit-Position: refs/heads/master@{#9756}
47 files changed