Manual review shows that several more sources should be excluded for the
Chromium build. This is likely what's blocking
https://codereview.chromium.org/2022833002/
It was also discovered that the following were missing from GYP+GN:
webrtc/p2p/base/dtlstransport.h
webrtc/p2p/base/session.cc
webrtc/p2p/base/session.h
BUG=webrtc:4256
TBR=pthatcher@webrtc.org
NOTRY=True
NOPRESUBMIT=True
Review-Url: https://codereview.webrtc.org/2077883002
Cr-Commit-Position: refs/heads/master@{#13200}
5023d41cb4