[PhotosUI] Add Xcode 11 Beta 1 Binding (#6624)

* Adding xcode 11 beta 1-3 initial PhotosUI changes

* reverted a few changes

* adding in UIKitForMac Unavailable

src/photosui.cs

@@ -24,6 +24,8 @@ namespace PhotosUI {
 	[iOS (8, 0)]
 	[Mac (10, 13)]
 	[Protocol]
+	[Unavailable (PlatformName.UIKitForMac)]
+	[Advice ("This API is not available when using UIKit on macOS.")]
 #if !XAMCORE_4_0 && !TVOS && !MONOMAC
 	// According to documentation you're supposed to implement this protocol in a UIViewController subclass,
 	// which means a model (which does not inherit from UIViewController) is not useful.
@@ -471,6 +473,9 @@ namespace PhotosUI {
 	[iOS (8,0)]
 	[NoMac][NoTV]
 	[DisableDefaultCtor]
+	[Unavailable (PlatformName.UIKitForMac)]
+	[Advice ("This API is not available when using UIKit on macOS.")]
+	[Deprecated (PlatformName.iOS, 13, 0)]
 	[BaseType (typeof (NSExtensionContext))]
 	interface PHEditingExtensionContext
 	{

tests/xtro-sharpie/iOS-PhotosUI.todo

@@ -1 +0,0 @@
-!deprecated-attribute-missing! PHEditingExtensionContext missing a [Deprecated] attribute