Remove overrides folder.

This is a part of moving the overrides to Chromium. See bug comment #65 for all steps.

Depends on https://codereview.chromium.org/1357913002/

BUG=chromium:468375
TBR=tommi@webrtc.org

Review URL: https://codereview.webrtc.org/1350393003

Cr-Original-Commit-Position: refs/heads/master@{#10117}
Cr-Mirrored-From: https://chromium.googlesource.com/external/webrtc
Cr-Mirrored-Commit: 4a8e9c556af602ad6860df7d23247d0e2efe0cc2
5 files changed