[iOS 15] Add support for new delegate WKUIDelegate decideMediaCapturePermissionFor

[nanosonde]

Feature request / problem description
Every call to getUserMedia() from within a WKWebView instance will lead to a new permission popup requiring the user to allow/deny access to the camera and/or microphone. This is quite annoying from a user perspective.

Example use-case: I use an audio/video capable Home Assistant card to have an audio/video connection to my doorbell within HA lovelace UI.

Describe the solution you'd like
Implement the new delegate WKUIDelegate decideMediaCapturePermissionFor to handle getUserMedia() media capture permission requests so that the user does not get a permission prompt for camera/microphone with every call to getUserMedia() when loading or reloading a webpage from within an existing instance of WKWebView.

Additional context

1. Original bug report for iOS 14.3: https://bugs.webkit.org/show_bug.cgi?id=220416
2. Another related forum topic: https://developer.apple.com/forums/thread/669011
3. Presentation of the new delegate on WWDC 2021 at timestamp 14:40: https://developer.apple.com/videos/play/wwdc2021/10032/
4. A clarification about the new delegate in the Apple forum: https://developer.apple.com/forums/thread/682293
5. getUserMedia(): https://developer.mozilla.org/en-US/docs/Web/API/MediaDevices/getUserMedia
6. Somehow related issue: Add microphone access (NSMicrophoneUsageDescription) #1319

[zacwest]

Looks like this is declared as being supported back to iOS 14.5, but requires Xcode 13 to use it.

[zacwest]

These delegate methods are all over the place - some are async and some pass in a block for a decision handler. Probably best to wait until later in the Xcode 13 beta period before playing with it.

[idoodler]

I tried to implement it. Now the prompts are gone, but I don't get the orange recording indicator of iOS and I don't hear anything:/

[nanosonde]

I tried to implement it. Now the prompts are gone, but I don't get the orange recording indicator of iOS and I don't hear anything:/

What exactly have you tested where you do not hear anything?

[zacwest]

It looks like the only API they added for this in the iOS 15 release is:

- (void)webView:(WKWebView *)webView
requestMediaCapturePermissionForOrigin:(WKSecurityOrigin *)origin
initiatedByFrame:(WKFrameInfo *)frame
type:(WKMediaCaptureType)type
decisionHandler:(void (^)(WKPermissionDecision decision))decisionHandler;

which is documented (only in the headers, not in the actual docs, sigh) as:

If not implemented, the result is the same as calling the decisionHandler with WKPermissionDecisionPrompt.

This may behave as you'd like without any app-level changes.

[zacwest]

Oh I see, you'd like the app to always say yes so it doesn't always prompt. That also seems doable, assuming it is prompting correctly.