1436424 - Remove {fake: true} constraint

Status: NEW

(Core :: WebRTC: Audio/Video, task, P3)

Description

[Jan-Ivar Bruaroey [:jib] (needinfo? me)]

We currently expose fake internal camera and microphone output devices we use internally for testing to the web platform using a `fake` constraint in gUM:

    navigator.mediaDevices.getUserMedia({video: true, audio: true, fake: true});

This is non-standard functionality we should remove. The functionality will remain accessible using the "media.navigator.streams.fake;true" pref [1] for use in our tests and in things like web-platform-tests.

To do this, we need to also update various internal tests that still use {fake: true} and sometimes {fake:false} to twiddle the pref instead.

The web platform functionality lost is an audio track emitting a 1 kHz sine wave, and a video track emitting a 640x480 solid surface of slowly changing color, with some timestamp info encoded in the corner. This is trivial to replicate in JS these days with web audio and captureStream [2].

[1] https://searchfox.org/mozilla-central/rev/84cea84b12145d752e50ddca6be5462c38510e35/dom/media/MediaManager.cpp#2678-2679
[2] See https://blog.mozilla.org/webrtc/warm-up-with-replacetrack/ for a starting point.

Comment 1

[Paul Adenot (:padenot)]

We need to fix [0] as well.

[0]: https://github.com/webrtc/apprtc/blob/master/src/app_engine/apprtc.py#L94

Comment 2

[Jan-Ivar Bruaroey [:jib] (needinfo? me)]

Thanks, I've filed https://github.com/webrtc/apprtc/issues/533 on it.