Extension:EventLogging/sendBeacon

Send Beacon
We want to take advantage of the new SendBeacon API on EL. Some discussions about the how and when:

Epic bug discussion: https://bugzilla.wikimedia.org/show_bug.cgi?id=42815

Somewhat epic patch discussion: https://gerrit.wikimedia.org/r/#/c/162194/

Meeting notes for 10/3 meeting
Attending: Prateek, Timo, Matthew, Aaron, Sam, Nuria

There were two items we wanted to discuss: usage of sendBeaconAPI and whether it is appropriate to log page jumps the way we have been doing up to now. We only had time to discuss the 1st item of these two.

Decisions taken
We will run a small experiment using both sendBeacon and our regular login to asses support of API. As of this writing the API is 'alive' only in FF and available in Chrome under a flag. We will run the experiment for a while to gather both FF and Chrome data (we believe API will be available without a flag in the new Chrome release). Once we get results of this experiment we will decide whether we want to use sendBeacon when available.

Action Items

 * [Nuria] Will make ops request to setup CORS on EL endpoint
 * [Prateek] Code changes to patch https://gerrit.wikimedia.org/r/#/c/162194/ regarding naming of methods and documentation. The method name should not look like a polyfill.
 * [Matthew] Will set up experiment to gather data regarding SendBeacon behavior versus our actual logging method.