Reduce amount of unsafe on iOS (#2579)

* Use objc2::foundation CG types

* Add safe abstraction over UIApplication

* Add safe abstraction over UIDevice

* Add safe abstraction over UIScreen

* Add safe abstraction over UIWindow

* Add safe abstraction over UIViewController

* Add safe abstraction over UIView

* Appease clippy

src/platform_impl/ios/uikit/view_controller.rs

@@ -1,7 +1,8 @@
-use objc2::foundation::NSObject;
-use objc2::{extern_class, ClassType};
+use objc2::encode::{Encode, Encoding};
+use objc2::foundation::{NSObject, NSUInteger};
+use objc2::{extern_class, extern_methods, ClassType};
 
-use super::UIResponder;
+use super::{UIResponder, UIView};
 
 extern_class!(
     #[derive(Debug, PartialEq, Eq, Hash)]
@@ -12,3 +13,38 @@ extern_class!(
         type Super = UIResponder;
     }
 );
+
+extern_methods!(
+    unsafe impl UIViewController {
+        #[sel(attemptRotationToDeviceOrientation)]
+        pub fn attemptRotationToDeviceOrientation();
+
+        #[sel(setNeedsStatusBarAppearanceUpdate)]
+        pub fn setNeedsStatusBarAppearanceUpdate(&self);
+
+        #[sel(setNeedsUpdateOfHomeIndicatorAutoHidden)]
+        pub fn setNeedsUpdateOfHomeIndicatorAutoHidden(&self);
+
+        #[sel(setNeedsUpdateOfScreenEdgesDeferringSystemGestures)]
+        pub fn setNeedsUpdateOfScreenEdgesDeferringSystemGestures(&self);
+
+        #[sel(setView:)]
+        pub fn setView(&self, view: Option<&UIView>);
+    }
+);
+
+bitflags! {
+    pub struct UIInterfaceOrientationMask: NSUInteger {
+        const Portrait = 1 << 1;
+        const PortraitUpsideDown = 1 << 2;
+        const LandscapeRight = 1 << 3;
+        const LandscapeLeft = 1 << 4;
+        const Landscape = Self::LandscapeLeft.bits() | Self::LandscapeRight.bits();
+        const AllButUpsideDown = Self::Landscape.bits() | Self::Portrait.bits();
+        const All = Self::AllButUpsideDown.bits() | Self::PortraitUpsideDown.bits();
+    }
+}
+
+unsafe impl Encode for UIInterfaceOrientationMask {
+    const ENCODING: Encoding = NSUInteger::ENCODING;
+}