Manually check AVCaptureDevice access

[rholstad]

Simple change illustrating how the existing setup code can be modified to handle initial camera access denial.

[nathanfallet]

@rholstad Why did you declare a function setupCaptureDevice to call it only once in AVCaptureDevice.requestAccess? What about wrapping the original code directly inside AVCaptureDevice.requestAccess?

[rholstad]

@nathanfallet No reason.

[rholstad]

@nathanfallet fetched upstream changes, inlined the setupCaptureDevice function, and added a setNeedsStatusBarAppearanceUpdate call since I found that the status bar remained after the privacy alert was dismissed.

[twostraws]

Thank you!