EventSource is not compatible with most mobile devices

[oparoz]

EventSoure is a great way to send thumbnails as they're generated, but the problem is that it's not compatible with the most popular mobile platform: Android.

Here are 3 libraries to test as a replacement for the one found in core:

• https://github.com/Yaffle/EventSource
• https://github.com/amvtek/EventSource
• https://github.com/remy/polyfills/blob/master/EventSource.js

They're all available via bower

[oparoz]

As it turns out, the fallbacks implemented in OC_EventSource do work on mobile. The problems I experienced were due to OC requiring the browser to accept cookies for CSRF to work.