Chromium cannot see virtual webcam anymore

[Ashark]

It seems like chromium do not list virtual /dev/videoN devices anymore even when using reinsert-internal-webcam script or actually reinsering some physical webcam or restarting chromium.
It only displays usb web cameras.
You can open chrome://settings/content/camera in new tab and see, that it updates list of webcameras rather frequent. For example for me webcam dissappears immediately from list after ejecting, and appears after around 4 seconds after inserting.

Not sure if it is caused by browser update, I suspect maybe some other system component involved.
Versions when breakage already happened (ArchLinux packages): linux 4.15.3-1, chromium 63.0.3239.84-1

[Ashark]

Move a piece of README here until fixing

Chromium will not add virtual webcam to the list of availible webcams automatically. It will only happen when chromium will be completely restarted (i.e. all browser windows should be closed, not only hangouts window) or only after usb webcam was removed/inserted

    So I thought about several workaround of this:
    - Patch chromium to automatically update that list even if it is virtual webcam.
    - Just insert or remove any other usb webcam to your pc after creating virtual webcam. I have checked this, it works.
    - Simulate such action programmatically. I have found something about usb gadget, but did not checked it yet.
    - Unload uvcvideo driver then modprobe it again. Did not checked it yet.
    - Programmatically disable/enable internal laptop webcam. Then chromium will show virtual webcam in its list of available cameras. I used this method successfully. It is in reinsert-internal-webcam script.

[Ashark]

Items removed from Usage in Readme until fixing

• Edit PID and VID variables in reinsert-internal-webcam script according to your internal laptop webcam pid and vid (use lsusb).
  
• Run reinsert-internal-webcam script.