Stats example uses confusing variable names

[henbos]

https://w3c.github.io/webrtc-stats/#example-of-a-stats-application uses variable names that refer to both RTCStats (report) and RTCStatsReport (currentReport) as reports.

Clearly one is a report and one is a stats object. The former is clearly a report and the latter, well up for debate if this should be called stat or stats or statsObject. I don't really care as long as we don't call it a report.

Normally I wouldn't care that this example is using silly variable names, but apparently we have duplicated this confusion to both samples and CLs.

[fippo]

@henbos @jan-ivar lets move some of the discussion about divide-by-zero from #794 here

The current sample is old and the only cool thing it does is showing remoteId. But it does not call out divide-by-zero, does not explain why a previous report could go away, why the timestamp might not get updated etc. Oh and }) is a syntax error.

Calculating STUN RTT is a much easier thing to explain and can be used to show both instantaneous and cumulative measures.
For showing map traversal "what codec is being sent" is my favorite

[fippo]

at minimum we should replace the current example with the webrtc-pc one:
https://w3c.github.io/webrtc-pc/#getstats-example

[fippo]

MDN is confused too:
https://developer.mozilla.org/en-US/docs/Web/API/RTCPeerConnection/getStats
"This works by calling getStats(), then, when the promise is resolved, iterates over the RTCStatsReport objects on the returned RTCStatsReport"