[webrtc-stats] framesDecoded is on both "receiver" and "inbound-rtp" stats. Redundant. (#392)

jan-ivar has just created a new issue for https://github.com/w3c/webrtc-stats:

== framesDecoded is on both "receiver" and "inbound-rtp" stats. Redundant. ==
Their descriptions are identical. Where do we want it to live?
 1. https://w3c.github.io/webrtc-stats/#dom-rtcinboundrtpstreamstats-framesdecoded
 2. https://w3c.github.io/webrtc-stats/#dom-rtcvideoreceiverstats-framesdecoded

The inverse [framesEncoded](https://w3c.github.io/webrtc-stats/#dom-rtcoutboundrtpstreamstats-framesencoded) lives on `"outbound-rtp"`, which suggests (1).

But then [framesDropped](https://w3c.github.io/webrtc-stats/#dom-rtcvideoreceiverstats-framesdropped) lives on (2).

I'm trying not to be influenced by (2) having a dedicated video type.

Please view or discuss this issue at https://github.com/w3c/webrtc-stats/issues/392 using your GitHub account