[webrtc-pc] new commits pushed by alvestrand

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

* cleanup connectionstates
  by Jonas Olsson
https://github.com/w3c/webrtc-pc/commit/7f406d303a13ca30f201147b3e30bd7397b4499a

* Merge pull request #2036 from jonasesolsson/connection-state

Cleanup connection states.
  by Harald Alvestrand
https://github.com/w3c/webrtc-pc/commit/98feb9c700b89e7b9db8182af41aae1ff2e9e46a