Check supported interface orientations into account when rotating device/view layout

[julianrex]

See #13895

Since we don't provide a view controller or hooks for -[UIViewController viewWillTransitionToSize:withTransitionCoordinator:] we call [[UIDevice currentDevice] beginGeneratingDeviceOrientationNotifications] to detect device rotation.

However, we do not currently take into account the application's (and view controller's) supported interface orientations. And as such, layoutSubviews is called on each device rotation (even if the UI doesn't change).

This experimental branch/PR adds those checks:

From the Apple documentation for UIViewController.supportedInterfaceOrientations:

When the user changes the device orientation, the system calls this method on the root view controller or the topmost presented view controller that fills the window. If the view controller supports the new orientation, the window and view controller are rotated to the new orientation. This method is only called if the view controller's shouldAutorotate method returns YES.

This PR checks the top-most view controller's shouldAutorotate...

Override this method to report all of the orientations that the view controller supports. [...] The system intersects the view controller's supported orientations with the app's supported orientations (as determined by the Info.plist file or the app delegate's application:supportedInterfaceOrientationsForWindow: method) and the device's supported orientations to determine whether to rotate.

... and also checks that view controller's supportedInterfaceOrientations intersected with the orientations provided by the application (as noted above).

Note: this PR checks the top-most view controller rather than the view controller that hosts the map view.

[julianrex]

@friedbunny thoughts?

[friedbunny]

LGTM, besides the changelog.

[friedbunny]

Should we get rid of this line?

[julianrex]

As a follow-up, we're investigating whether we even need deviceOrientationDidChange: anymore. See #14661