feat: add media access apis for mojave

[codebytere]

Description of Change

This PR adds new APIs to control new media privacy and consent rules introduced in MacOS Mojave. Namely:

systemPreferences.getMediaAccessStatus(mediaType)
systemPreferences.askForMediaAccess(mediaType)

Apple Docs:

• [AVCaptureDevice authorizationStatusForMediaType:]
• [AVCaptureDevice requestAccessForMediaType:completionHandler:]
• AVAuthorizationStatus

Checklist

• PR description included and stakeholders cc'd
• npm test passes
• relevant documentation is changed or added
• PR title follows semantic commit guidelines

Release Notes

Notes: Added media access APIs for macOS Mojave

[groundwater]

We're 👍 on porting to 4.x post-merge if:

• works with MAS
• Works on older macos versions

However, there is still outstanding debate on the actual API cc @nornagon @codebytere

[miniak]

We should return an enum, with all the 4 possible values as returned by the OS API. Being able to distinguish between denied and restricted is quite important to be able to show appropriate UI to the users of the apps.

[miniak]

Also I think the API should just be a thin wrapper over the OS APIs. I would definitely not show any message boxes, let the app decide how to present that to the user.

Something like this:

getMediaAccessStatus(mediaType: 'audio' | 'video'): 'not-determined' | 'allowed' | 'denied' | 'restricted'
requestMediaAccess(mediaType: 'audio' | 'video'): Promise<boolean>

[miniak]

If you insist on providing a conveniece API, I would expose both the raw API, which provides all the states and just add an additional method to do that, which can be inplemented in JS using the low level APIs. This way the C++ code can stay much simpler and without any business logic

[rspeyer]

+1 on @miniak's feedback - I think this API should do less to transform the data and be treated as more of a passthrough of Apple's data

[alexeykuzmin]

Questions are up there.

[codebytere]

This should be ready for review again, i've addressed all the above comments and simplified the impl to remove opinionated behaviors 😀

[miniak]

@alexeykuzmin, @nornagon can you please check the refactored version?

[alexeykuzmin]

👍

[miniak]

Verified to work properly on macOS 10.13

cc @groundwater

[miniak]

@rspeyer can you sign-off as well?

[release-clerk]

Release Notes Persisted

Added media access APIs for macOS Mojave

[trop]

I have automatically backported this PR to "4-0-x", please check out #15948

[james-pellow]

I believe we still need to make default additions to the Electron.app/Contents/Info.plist file. Using this API in development is challenging given that NSMicrophoneUsageDescription and/or NSCameraUsageDescription are required by osx for the [AVCaptureDevice requestAccessForMediaType:type] call to succeed. Otherwise the app just crashes. I've temporarily solved this in my app by manually adding the keys to Electron.app/Contents/Info.plist in node_modules, then I call open ./node_modules/electron/dist/Electron.app -n -W --args $(pwd) to launch the app. This all still feels messy, and I doubt its what most uses are going to want to have to deal with. At least adding the default keys to Info.plist would help. Thoughts?

[nornagon]

Perhaps we can add some default generic strings to Info.plist? That's how chrome does it (2).

[codebytere]

good plan, i'll look into doing that today!