WebRTC spec errata (regarding states)

Some questions came up the other day regarding the current spec language
regarding the various state enums and callbacks. Looking it over, I see
that not all of what was agreed upon made it into the spec. Below is a set
of minor issues I noticed while reviewing.

References:
- State proposal:
https://docs.google.com/document/d/13TYiNSEmFkB7IeNLEJFxI0xMNk8q_LhXE_hbvFbXRTU/edit
- Dec teleconf minutes: http://www.w3.org/2012/12/13-webrtc-minutes.html


   1. RTCSignalingState
   1. 4.3.1, list 3, bullet 4:
      The transition to "stable" state, or any other signaling state, only
      occurs via calls to setLocalDescription or setRemoteDescription.
It is not
      connected with the ICE state transitions.
      2. 4.3.2.1: onopen
      We agreed to remove this callback, as it is no longer meaningful, and
      redundant with onsignalingstatechange.
      3. 4.3.2.1: onstatechange
      The correct name for this callback is onsignalingstatechange.
      4. 4.3.2.2: setLocalDescription
      The description for this function should indicate that it triggers a
      signaling state change. It should also indicate that an INVALID_STATE
      exception is triggered if the wrong SessionDescription.type is
supplied for
      the current state.
      5. 4.3.2.2: setRemoteDescription
      The description for this function should indicate that it triggers a
      signaling state change. It should also indicate that an INVALID_STATE
      exception is triggered if the wrong SessionDescription.type is
supplied for
      the current state.
   2. RTCIceConnectionState
      1. 4.3.2: onicechange
      The correct name for this callback is oniceconnectionstatechange.
      2. 4.4.3: RTCIceState
      The enum name is incorrect; it should be RTCIceConnectionState. Also,
      the initial state should be "new", like RTCIceGatheringState, not
      "starting".
   3. RTCIceGatheringState
      1. 4.3.2.1: ongatheringchange
      We decided that this callback is not needed; the necessary
      information can be gotten from onicecandidate.
      2. 4.3.2.1: onicecandidate
      The description for this callback should indicate that it is invoked
      with a null argument when gathering completes. Prior to dispatching this
      null callback, the iceGatheringState will be set to "completed".
      3. 4.3.2.2: setLocalDescription
      The description for this function should indicate that it causes a
      transition of the gathering state from "new", to "gathering", if that is
      the current state, and the local description contains at least
one m= line.
      Also, if a local description is supplied that contains a different set of
      ICE credentials, this will trigger an ICE restart, and change the ICE
      gathering state to "gathering".