[Foundation] Unify a NSAttributedString few constructor implementations.

Unify the code for the following constructors:

+ NSAttributedString (NSData data, NSDictionary options, out NSDictionary resultDocumentAttributes, ref/out NSError error);
+ NSAttributedString (NSUrl url, NSAttributedStringDocumentAttributes options, out NSDictionary resultDocumentAttributes, ref/out NSError error);
+ NSAttributedString (NSData data, NSAttributedStringDocumentAttributes options, out NSDictionary resultDocumentAttributes, ref/out NSError error);

These functions use 'ref' arguments instead of 'out' arguments for mobile
platforms (likely due to the generator not having proper 'out' parameter
support when these functions were implemented), so improve to use 'out'
parameters in XAMCORE_5_0 (and macOS, where they already use 'out'
parameters).

Also fix nullability.

Ref: xamarin#15216

src/foundation.cs

@@ -332,23 +332,6 @@ partial interface NSAttributedString : NSCoding, NSMutableCopying, NSSecureCodin
 		[Export ("initWithString:")]
 		NativeHandle Constructor (string str);
 
-#if !MONOMAC
-		[NoMac]
-		[iOS (7,0)]
-		[Wrap ("this (url, options.GetDictionary ()!, out resultDocumentAttributes, ref error)")]
-		NativeHandle Constructor (NSUrl url, NSAttributedStringDocumentAttributes options, out NSDictionary resultDocumentAttributes, ref NSError error);
-
-		[NoMac]
-		[iOS (7,0)]
-		[Export ("initWithData:options:documentAttributes:error:")]
-		NativeHandle Constructor (NSData data, [NullAllowed] NSDictionary options, out NSDictionary resultDocumentAttributes, ref NSError error);
-
-		[NoMac]
-		[iOS (7,0)]
-		[Wrap ("this (data, options.GetDictionary ()!, out resultDocumentAttributes, ref error)")]
-		NativeHandle Constructor (NSData data, NSAttributedStringDocumentAttributes options, out NSDictionary resultDocumentAttributes, ref NSError error);
-#endif
-
 		[Export ("initWithString:attributes:")]
 		[EditorBrowsable (EditorBrowsableState.Advanced)]
 		NativeHandle Constructor (string str, [NullAllowed] NSDictionary attributes);
@@ -369,11 +352,30 @@ partial interface NSAttributedString : NSCoding, NSMutableCopying, NSSecureCodin
 		NativeHandle Constructor (NSUrl url, NSDictionary options, out NSDictionary resultDocumentAttributes, out NSError error);
 #endif
 
-#if MONOMAC
-		[NoiOS][NoMacCatalyst][NoWatch][NoTV]
 		[Export ("initWithData:options:documentAttributes:error:")]
-		NativeHandle Constructor (NSData data, [NullAllowed] NSDictionary options, out NSDictionary docAttributes, out NSError error);
+#if __MACOS__ || XAMCORE_5_0
+		NativeHandle Constructor (NSData data, NSDictionary options, out NSDictionary resultDocumentAttributes, out NSError error);
+#else
+		NativeHandle Constructor (NSData data, NSDictionary options, out NSDictionary resultDocumentAttributes, ref NSError error);
+#endif
 
+#if __MACOS__ || XAMCORE_5_0
+		[Wrap ("this (url, options.GetDictionary ()!, out resultDocumentAttributes, out error)")]
+		NativeHandle Constructor (NSUrl url, NSAttributedStringDocumentAttributes options, out NSDictionary resultDocumentAttributes, out NSError error);
+#else
+		[Wrap ("this (url, options.GetDictionary ()!, out resultDocumentAttributes, ref error)")]
+		NativeHandle Constructor (NSUrl url, NSAttributedStringDocumentAttributes options, out NSDictionary resultDocumentAttributes, ref NSError error);
+#endif
+
+#if __MACOS__ || XAMCORE_5_0
+		[Wrap ("this (data, options.GetDictionary ()!, out resultDocumentAttributes, out error)")]
+		NativeHandle Constructor (NSData data, NSAttributedStringDocumentAttributes options, out NSDictionary resultDocumentAttributes, out NSError error);
+#else
+		[Wrap ("this (data, options.GetDictionary ()!, out resultDocumentAttributes, ref error)")]
+		NativeHandle Constructor (NSData data, NSAttributedStringDocumentAttributes options, out NSDictionary resultDocumentAttributes, ref NSError error);
+#endif
+
+#if MONOMAC
 		[NoiOS][NoMacCatalyst][NoWatch][NoTV]
 		[Export ("initWithDocFormat:documentAttributes:")]
 		NativeHandle Constructor(NSData wordDocFormat, out NSDictionary docAttributes);
@@ -386,14 +388,6 @@ partial interface NSAttributedString : NSCoding, NSMutableCopying, NSSecureCodin
 		[Export ("drawWithRect:options:")]
 		void DrawString (CGRect rect, NSStringDrawingOptions options);	
 
-		[NoiOS][NoMacCatalyst][NoWatch][NoTV]
-		[Wrap ("this (url, options.GetDictionary ()!, out resultDocumentAttributes, out error)")]
-		NativeHandle Constructor (NSUrl url, NSAttributedStringDocumentAttributes options, out NSDictionary resultDocumentAttributes, out NSError error);
-
-		[NoiOS][NoMacCatalyst][NoWatch][NoTV]
-		[Wrap ("this (data, options.GetDictionary ()!, out resultDocumentAttributes, out error)")]
-		NativeHandle Constructor (NSData data, NSAttributedStringDocumentAttributes options, out NSDictionary resultDocumentAttributes, out NSError error);
-
 		[NoiOS][NoMacCatalyst][NoWatch][NoTV]
 		[Deprecated (PlatformName.MacOSX, 10, 11, message: "Use 'NSAttributedString (NSUrl, NSDictionary, out NSDictionary, ref NSError)' instead.")]
 		[Export ("initWithPath:documentAttributes:")]

tests/xtro-sharpie/api-annotations-dotnet/iOS-UIKit.ignore

@@ -60,7 +60,6 @@
 !extra-null-allowed! 'System.Boolean UIKit.NSLayoutManagerDelegate::ShouldSetLineFragmentRect(UIKit.NSLayoutManager,CoreGraphics.CGRect&,CoreGraphics.CGRect&,System.Runtime.InteropServices.NFloat&,UIKit.NSTextContainer,Foundation.NSRange)' has a extraneous [NullAllowed] on parameter #2
 !extra-null-allowed! 'System.Boolean UIKit.NSLayoutManagerDelegate::ShouldSetLineFragmentRect(UIKit.NSLayoutManager,CoreGraphics.CGRect&,CoreGraphics.CGRect&,System.Runtime.InteropServices.NFloat&,UIKit.NSTextContainer,Foundation.NSRange)' has a extraneous [NullAllowed] on parameter #3
 !extra-null-allowed! 'System.Boolean UIKit.UIApplication::CanOpenUrl(Foundation.NSUrl)' has a extraneous [NullAllowed] on parameter #0
-!extra-null-allowed! 'System.Void Foundation.NSAttributedString::.ctor(Foundation.NSData,Foundation.NSDictionary,Foundation.NSDictionary&,Foundation.NSError&)' has a extraneous [NullAllowed] on parameter #1
 !extra-null-allowed! 'System.Void UIKit.UIAccessibilityCustomAction::.ctor(Foundation.NSAttributedString,UIKit.UIAccessibilityCustomActionHandler)' has a extraneous [NullAllowed] on parameter #1
 !extra-null-allowed! 'System.Void UIKit.UIAccessibilityCustomAction::.ctor(System.String,UIKit.UIAccessibilityCustomActionHandler)' has a extraneous [NullAllowed] on parameter #1
 !extra-null-allowed! 'System.Void UIKit.UIAccessibilityCustomAction::set_Name(System.String)' has a extraneous [NullAllowed] on parameter #0

tests/xtro-sharpie/api-annotations-dotnet/macOS-AppKit.ignore

@@ -267,7 +267,6 @@
 !extra-null-allowed! 'System.Void AppKit.NSView::set_ContentFilters(CoreImage.CIFilter[])' has a extraneous [NullAllowed] on parameter #0
 !extra-null-allowed! 'System.Void AppKit.NSView::WillRemoveSubview(AppKit.NSView)' has a extraneous [NullAllowed] on parameter #0
 !extra-null-allowed! 'System.Void Foundation.NSAttributedString::.ctor(Foundation.NSData,Foundation.NSDictionary,Foundation.NSDictionary&)' has a extraneous [NullAllowed] on parameter #1
-!extra-null-allowed! 'System.Void Foundation.NSAttributedString::.ctor(Foundation.NSData,Foundation.NSDictionary,Foundation.NSDictionary&,Foundation.NSError&)' has a extraneous [NullAllowed] on parameter #1
 
 # Initial result from new rule missing-null-allowed
 !missing-null-allowed! 'AppKit.INSPasteboardWriting AppKit.NSCollectionViewDelegate::PasteboardWriterForItem(AppKit.NSCollectionView,System.UIntPtr)' is missing an [NullAllowed] on return type

tests/xtro-sharpie/api-annotations-dotnet/tvOS-UIKit.ignore

@@ -101,7 +101,6 @@
 !extra-null-allowed! 'System.Boolean UIKit.NSLayoutManagerDelegate::ShouldSetLineFragmentRect(UIKit.NSLayoutManager,CoreGraphics.CGRect&,CoreGraphics.CGRect&,System.Runtime.InteropServices.NFloat&,UIKit.NSTextContainer,Foundation.NSRange)' has a extraneous [NullAllowed] on parameter #2
 !extra-null-allowed! 'System.Boolean UIKit.NSLayoutManagerDelegate::ShouldSetLineFragmentRect(UIKit.NSLayoutManager,CoreGraphics.CGRect&,CoreGraphics.CGRect&,System.Runtime.InteropServices.NFloat&,UIKit.NSTextContainer,Foundation.NSRange)' has a extraneous [NullAllowed] on parameter #3
 !extra-null-allowed! 'System.Boolean UIKit.UIApplication::CanOpenUrl(Foundation.NSUrl)' has a extraneous [NullAllowed] on parameter #0
-!extra-null-allowed! 'System.Void Foundation.NSAttributedString::.ctor(Foundation.NSData,Foundation.NSDictionary,Foundation.NSDictionary&,Foundation.NSError&)' has a extraneous [NullAllowed] on parameter #1
 !extra-null-allowed! 'System.Void UIKit.UIAccessibilityCustomAction::.ctor(Foundation.NSAttributedString,UIKit.UIAccessibilityCustomActionHandler)' has a extraneous [NullAllowed] on parameter #1
 !extra-null-allowed! 'System.Void UIKit.UIAccessibilityCustomAction::.ctor(System.String,UIKit.UIAccessibilityCustomActionHandler)' has a extraneous [NullAllowed] on parameter #1
 !extra-null-allowed! 'System.Void UIKit.UIAccessibilityCustomAction::set_Name(System.String)' has a extraneous [NullAllowed] on parameter #0

tests/xtro-sharpie/iOS-UIKit.ignore

@@ -82,7 +82,6 @@
 !extra-null-allowed! 'System.Boolean UIKit.NSLayoutManagerDelegate::ShouldSetLineFragmentRect(UIKit.NSLayoutManager,CoreGraphics.CGRect&,CoreGraphics.CGRect&,System.nfloat&,UIKit.NSTextContainer,Foundation.NSRange)' has a extraneous [NullAllowed] on parameter #2
 !extra-null-allowed! 'System.Boolean UIKit.NSLayoutManagerDelegate::ShouldSetLineFragmentRect(UIKit.NSLayoutManager,CoreGraphics.CGRect&,CoreGraphics.CGRect&,System.nfloat&,UIKit.NSTextContainer,Foundation.NSRange)' has a extraneous [NullAllowed] on parameter #3
 !extra-null-allowed! 'System.Boolean UIKit.UIApplication::CanOpenUrl(Foundation.NSUrl)' has a extraneous [NullAllowed] on parameter #0
-!extra-null-allowed! 'System.Void Foundation.NSAttributedString::.ctor(Foundation.NSData,Foundation.NSDictionary,Foundation.NSDictionary&,Foundation.NSError&)' has a extraneous [NullAllowed] on parameter #1
 !extra-null-allowed! 'System.Void UIKit.UIAccessibilityCustomAction::.ctor(Foundation.NSAttributedString,UIKit.UIAccessibilityCustomActionHandler)' has a extraneous [NullAllowed] on parameter #1
 !extra-null-allowed! 'System.Void UIKit.UIAccessibilityCustomAction::.ctor(System.String,UIKit.UIAccessibilityCustomActionHandler)' has a extraneous [NullAllowed] on parameter #1
 !extra-null-allowed! 'System.Void UIKit.UIAccessibilityCustomAction::set_Name(System.String)' has a extraneous [NullAllowed] on parameter #0

tests/xtro-sharpie/macOS-AppKit.ignore

@@ -367,7 +367,6 @@
 !extra-null-allowed! 'System.Void AppKit.NSView::set_ContentFilters(CoreImage.CIFilter[])' has a extraneous [NullAllowed] on parameter #0
 !extra-null-allowed! 'System.Void AppKit.NSView::WillRemoveSubview(AppKit.NSView)' has a extraneous [NullAllowed] on parameter #0
 !extra-null-allowed! 'System.Void Foundation.NSAttributedString::.ctor(Foundation.NSData,Foundation.NSDictionary,Foundation.NSDictionary&)' has a extraneous [NullAllowed] on parameter #1
-!extra-null-allowed! 'System.Void Foundation.NSAttributedString::.ctor(Foundation.NSData,Foundation.NSDictionary,Foundation.NSDictionary&,Foundation.NSError&)' has a extraneous [NullAllowed] on parameter #1
 
 # Initial result from new rule missing-null-allowed
 !missing-null-allowed! 'AppKit.INSPasteboardWriting AppKit.NSCollectionViewDelegate::PasteboardWriterForItem(AppKit.NSCollectionView,System.nuint)' is missing an [NullAllowed] on return type

tests/xtro-sharpie/tvOS-UIKit.ignore

@@ -113,7 +113,6 @@
 !extra-null-allowed! 'System.Boolean UIKit.NSLayoutManagerDelegate::ShouldSetLineFragmentRect(UIKit.NSLayoutManager,CoreGraphics.CGRect&,CoreGraphics.CGRect&,System.nfloat&,UIKit.NSTextContainer,Foundation.NSRange)' has a extraneous [NullAllowed] on parameter #2
 !extra-null-allowed! 'System.Boolean UIKit.NSLayoutManagerDelegate::ShouldSetLineFragmentRect(UIKit.NSLayoutManager,CoreGraphics.CGRect&,CoreGraphics.CGRect&,System.nfloat&,UIKit.NSTextContainer,Foundation.NSRange)' has a extraneous [NullAllowed] on parameter #3
 !extra-null-allowed! 'System.Boolean UIKit.UIApplication::CanOpenUrl(Foundation.NSUrl)' has a extraneous [NullAllowed] on parameter #0
-!extra-null-allowed! 'System.Void Foundation.NSAttributedString::.ctor(Foundation.NSData,Foundation.NSDictionary,Foundation.NSDictionary&,Foundation.NSError&)' has a extraneous [NullAllowed] on parameter #1
 !extra-null-allowed! 'System.Void UIKit.UIAccessibilityCustomAction::.ctor(Foundation.NSAttributedString,UIKit.UIAccessibilityCustomActionHandler)' has a extraneous [NullAllowed] on parameter #1
 !extra-null-allowed! 'System.Void UIKit.UIAccessibilityCustomAction::.ctor(System.String,UIKit.UIAccessibilityCustomActionHandler)' has a extraneous [NullAllowed] on parameter #1
 !extra-null-allowed! 'System.Void UIKit.UIAccessibilityCustomAction::set_Name(System.String)' has a extraneous [NullAllowed] on parameter #0

tests/xtro-sharpie/watchOS-UIKit.ignore

@@ -25,7 +25,6 @@
 !missing-pinvoke! UIImageSymbolWeightForFontWeight is not bound
 
 # Initial result from new rule extra-null-allowed
-!extra-null-allowed! 'System.Void Foundation.NSAttributedString::.ctor(Foundation.NSData,Foundation.NSDictionary,Foundation.NSDictionary&,Foundation.NSError&)' has a extraneous [NullAllowed] on parameter #1
 !extra-null-allowed! 'System.Void UIKit.UIBezierPath::set_CGPath(CoreGraphics.CGPath)' has a extraneous [NullAllowed] on parameter #0
 
 # Initial result from new rule missing-null-allowed