Browse does not handle the new user media permission requests

[quozl]

On Ubuntu 18.04 with Browse 7cfd9f251fd9e5586d3323c50b760f50f2e7eae1 and v202, scratch.mit.edu online editor v3.0 does play sound fine, but does not record sound. When an attempt is made, a dialog from the web app is shown, but it is insensitive. There is no WebKit2.UserMediaPermissionRequest sent. Console shows an internationalisation error in the web app;

projects.bundle.js:68:13595
Unhandled Promise Rejection:
Invariant Violation: 
[React Intl] An `id` must be provided to format a message

Reproducer:

• start Browse, open https://scratch.mit.edu/, click on Create, await loading,
• click on Sound (purple circle),
• click on Meow in play sound, and select Record ...

Attemping to bisect by wrapper, MiniBrowser from libwebkit2gtk-4.0-37 does not render the editor at all.

Works fine with Firefox, which pops up a permission request at this time. If the permission request is refused, the editor remains in the same state as shown by the screenshot above.

https://www.html5rocks.com/en/tutorials/getusermedia/intro references an audio record demonstration at http://webaudiodemos.appspot.com/AudioRecorder/index.html which likewise does not work.

So the cause is a failure to receive and handle the permission request.

[quozl]

Also occurs on Fedora-SoaS-Live-x86_64-Rawhide-20190213.n.0.iso with

• Browse (as described above), and
• Epiphany (with popup message "Cloud not start recording").

Browse and Epiphany are both web browsers that implement WebKit.

Browse is correctly subscribing to WebKit permission requests.

This problem is caused by WebKit, and nothing we do in Browse will fix it. Any further work on the problem may have to happen with WebKit.

[quozl]

Tracking at WebKit as 194805. It appears to be a licensing corner case with the use of an SSL implementation. No progress is expected.