[webrtc-pc] new commits pushed by alvestrand

The following commits were just pushed by alvestrand to https://github.com/w3c/webrtc-pc:

* Maximum message size slightly incorrect

Fix for Issue https://github.com/w3c/webrtc-pc/issues/1700
  by Bernard Aboba
https://github.com/w3c/webrtc-pc/commit/fd427e4cae50767718fbdb7ffc8e61bd29c1fe3f

* Merge pull request #1713 from w3c/issue-1700-patch

Maximum message size slightly incorrect
  by Harald Alvestrand
https://github.com/w3c/webrtc-pc/commit/50148b6fda952c7b4c67bfda5abe576759728a99