[generator] Revert changes to [UnsupportedOSPlatform] (#1367)

Context: #1313
Context: dotnet/android#10509

Reverts:

* 28d6905
* 1cfb4f4

To reduce the chance of breakage in .NET 10, going to revert this feature on `release/10.0.1xx`.

The changes will be left in `main` along with the fix:

* #1366

Author: jonathanpeppers

tests/generator-Tests/Unit-Tests/CodeGeneratorTests.cs

@@ -1406,69 +1406,6 @@ public void SupportedOSPlatformConstFields ()
 			StringAssert.Contains ("[global::System.Runtime.Versioning.SupportedOSPlatformAttribute (\"android30.0\")]", builder.ToString (), "Should contain SupportedOSPlatform!");
 		}
 
-		[Test]
-		public void UnsupportedOSPlatform ()
-		{
-			var klass = SupportTypeBuilder.CreateClass ("java.code.MyClass", options);
-			klass.ApiRemovedSince = new AndroidSdkVersion (30);
-
-			generator.Context.ContextTypes.Push (klass);
-			generator.WriteType (klass, string.Empty, new GenerationInfo ("", "", "MyAssembly"));
-			generator.Context.ContextTypes.Pop ();
-
-			StringAssert.Contains ("[global::System.Runtime.Versioning.UnsupportedOSPlatformAttribute (\"android30.0\")]", builder.ToString (), "Should contain UnsupportedOSPlatform!");
-		}
-
-		[Test]
-		public void UnsupportedOSPlatformConstFields ()
-		{
-			var klass = new TestClass ("java.lang.Object", "com.mypackage.foo");
-			var field = new TestField ("java.lang.String", "bar").SetConstant ("MY_VALUE");
-
-			field.ApiRemovedSince = new AndroidSdkVersion (30);
-
-			klass.Fields.Add (field);
-
-			generator.Context.ContextTypes.Push (klass);
-			generator.WriteType (klass, string.Empty, new GenerationInfo ("", "", "MyAssembly"));
-			generator.Context.ContextTypes.Pop ();
-
-			StringAssert.Contains ("[global::System.Runtime.Versioning.UnsupportedOSPlatformAttribute (\"android30.0\")]", builder.ToString (), "Should contain UnsupportedOSPlatform!");
-		}
-
-
-		[Test]
-		public void UnsupportedOSPlatformIgnoresMethodOverrides ()
-		{
-			// Given:
-			// public class TextView {
-			//   public Object doThing () { ... }
-			// }
-			// public class TextView2 : TextView {
-			//   public Object doThing () { ... }   // removed-since = 30
-			// }
-			// We should not write [UnsupportedOSPlatform] on TextView2.doThing (), because the base method isn't "removed".
-			var xml = @$"<api>
-			  <package name='java.lang' jni-name='java/lang'>
-			    <class abstract='false' deprecated='not deprecated' final='false' name='Object' static='false' visibility='public' jni-signature='Ljava/lang/Object;' />
-			  </package>
-			  <package name='android.widget' jni-name='android/widget'>
-			    <class abstract='false' deprecated='not deprecated' extends='java.lang.Object' extends-generic-aware='java.lang.Object' final='false' name='TextView' static='false' visibility='public'>
-			       <method abstract='false' deprecated='not deprecated' final='false' name='doThing' bridge='false' native='false' return='java.lang.Object' static='false' synchronized='false' synthetic='false' visibility='public' />
-			     </class>
-			    <class abstract='false' deprecated='not deprecated' extends='android.widget.TextView' extends-generic-aware='java.lang.Object' final='false' name='TextView2' static='false' visibility='public'>
-			       <method abstract='false' deprecated='not deprecated' final='false' name='doThing' bridge='false' native='false' return='java.lang.Object' static='false' synchronized='false' synthetic='false' visibility='public' removed-since='30' />
-			     </class>
-			  </package>
-			</api>";
-
-			var gens = ParseApiDefinition (xml);
-			var klass = gens.Single (g => g.Name == "TextView2");
-			var actual = GetGeneratedTypeOutput (klass);
-
-			StringAssert.DoesNotContain ("[global::System.Runtime.Versioning.UnsupportedOSPlatformAttribute (\"android30.0\")]", actual, "Should contain UnsupportedOSPlatform!");
-		}
-
 		[Test]
 		public void StringPropertyOverride ([Values ("true", "false")] string final)
 		{

tests/generator-Tests/Unit-Tests/XmlApiImporterTests.cs

@@ -51,15 +51,6 @@ public void CreateClass_CorrectApiSinceOverridePackage ()
 			Assert.AreEqual (9, klass.ApiAvailableSince.ApiLevel);
 		}
 
-		[Test]
-		public void CreateClass_CorrectApiRemoved ()
-		{
-			var xml = XDocument.Parse ("<package name='com.example.test' jni-name='com/example/test'><class name='myclass' removed-since='7' /></package>");
-			var klass = XmlApiImporter.CreateClass (xml.Root, xml.Root.Element ("class"), opt);
-
-			Assert.AreEqual (7, klass.ApiRemovedSince.ApiLevel);
-		}
-
 		[Test]
 		public void CreateCtor_EnsureValidName ()
 		{

tools/generator/ApiVersionsSupport.cs

@@ -20,7 +20,6 @@ public static class ApiVersionsSupport
 		public interface IApiAvailability
 		{
 			AndroidSdkVersion ApiAvailableSince { get; set; }
-			AndroidSdkVersion ApiRemovedSince { get; set; }
 		}
 
 		static IEnumerable<GenBase> FlattenGens (IEnumerable<GenBase> gens)

tools/generator/Java.Interop.Tools.Generator.Importers/XmlApiImporter.cs

@@ -159,7 +159,6 @@ public static Ctor CreateCtor (GenBase declaringType, XElement elem, CodeGenerat
 			var ctor = new Ctor (declaringType) {
 				AnnotatedVisibility = elem.XGetAttribute ("annotated-visibility"),
 				ApiAvailableSince = declaringType.ApiAvailableSince,
-				ApiRemovedSince = declaringType.ApiRemovedSince,
 				CustomAttributes = elem.XGetAttribute ("customAttributes"),
 				Deprecated = elem.Deprecated (),
 				DeprecatedSince = elem.XGetAttributeAsAndroidSdkVersionOrNull ("deprecated-since"),
@@ -212,7 +211,6 @@ public static Field CreateField (GenBase declaringType, XElement elem, CodeGener
 			var field = new Field {
 				AnnotatedVisibility = elem.XGetAttribute ("annotated-visibility"),
 				ApiAvailableSince = declaringType.ApiAvailableSince,
-				ApiRemovedSince = declaringType.ApiRemovedSince,
 				DeprecatedComment = elem.XGetAttribute ("deprecated"),
 				DeprecatedSince = elem.XGetAttributeAsAndroidSdkVersionOrNull ("deprecated-since"),
 				IsAcw = true,
@@ -371,7 +369,6 @@ public static Method CreateMethod (GenBase declaringType, XElement elem, CodeGen
 			var method = new Method (declaringType) {
 				AnnotatedVisibility = elem.XGetAttribute ("annotated-visibility"),
 				ApiAvailableSince = declaringType.ApiAvailableSince,
-				ApiRemovedSince = declaringType.ApiRemovedSince,
 				ArgsType = elem.Attribute ("argsType")?.Value,
 				CustomAttributes = elem.XGetAttribute ("customAttributes"),
 				Deprecated = elem.Deprecated (),
@@ -518,12 +515,9 @@ static XElement GetPreviousClass (XNode n, string nameValue)
 		// Elements need to be passed in the above order. (package, class, member)
 		static void FillApiSince (ApiVersionsSupport.IApiAvailability model, params XElement[] elems)
 		{
-			foreach (var elem in elems) {
+			foreach (var elem in elems)
 				if (AndroidSdkVersion.TryParse (elem.XGetAttribute ("api-since"), out var result))
 					model.ApiAvailableSince = result;
-				if (AndroidSdkVersion.TryParse (elem.XGetAttribute ("removed-since"), out var removed))
-					model.ApiRemovedSince = removed;
-			}
 		}
 
 		static bool IsObfuscatedName (int threshold, string name)

tools/generator/Java.Interop.Tools.Generator.ObjectModel/Field.cs

@@ -9,7 +9,6 @@ public class Field : ApiVersionsSupport.IApiAvailability, ISourceLineInfo
 		public string AnnotatedVisibility { get; set; }
 		public string Annotation { get; set; }
 		public AndroidSdkVersion ApiAvailableSince { get; set; }
-		public AndroidSdkVersion ApiRemovedSince { get; set; }
 		public string DeprecatedComment { get; set; }
 		public AndroidSdkVersion? DeprecatedSince { get; set; }
 		public bool IsAcw { get; set; }

tools/generator/Java.Interop.Tools.Generator.ObjectModel/GenBase.cs

@@ -188,8 +188,6 @@ IEnumerable<GenBase> Ancestors ()
 
 		public AndroidSdkVersion ApiAvailableSince { get; set; }
 
-		public AndroidSdkVersion ApiRemovedSince { get; set; }
-
 		public virtual ClassGen BaseGen => null;
 
 		public GenBase BaseSymbol =>
@@ -323,11 +321,6 @@ public void FixupMethodOverrides (CodeGenerationOptions opt)
 								m.DeprecatedSince = bm.DeprecatedSince;
 						}
 
-						// If a "removed" method overrides a "not removed" method, the method was
-						// likely moved to a base class, so don't mark it as removed.
-						if (m.ApiRemovedSince > 0 && bm.ApiRemovedSince == 0)
-							m.ApiRemovedSince = default;
-
 						break;
 					}
 				}

tools/generator/Java.Interop.Tools.Generator.ObjectModel/MethodBase.cs

@@ -16,7 +16,6 @@ protected MethodBase (GenBase declaringType)
 		public string AnnotatedVisibility { get; set; }
 		public string Annotation { get; internal set; }
 		public AndroidSdkVersion ApiAvailableSince { get; set; }
-		public AndroidSdkVersion ApiRemovedSince { get; set; }
 		public string AssemblyName { get; set; }
 		public GenBase DeclaringType { get; }
 		public string Deprecated { get; set; }

tools/generator/SourceWriters/Attributes/UnsupportedOSPlatformAttr.cs

@@ -308,10 +308,7 @@ public static void AddParameterListCallArgs (List<string> body, ParameterList pa
 		}
 
 		public static void AddSupportedOSPlatform (List<AttributeWriter> attributes, ApiVersionsSupport.IApiAvailability member, CodeGenerationOptions opt)
-		{
-			AddSupportedOSPlatform (attributes, member.ApiAvailableSince, opt);
-			AddUnsupportedOSPlatform (attributes, member.ApiRemovedSince, opt);
-		}
+			=> AddSupportedOSPlatform (attributes, member.ApiAvailableSince, opt);
 
 		public static void AddSupportedOSPlatform (List<AttributeWriter> attributes, AndroidSdkVersion since, CodeGenerationOptions opt)
 		{
@@ -321,13 +318,6 @@ public static void AddSupportedOSPlatform (List<AttributeWriter> attributes, And
 				attributes.Add (new SupportedOSPlatformAttr (since));
 		}
 
-		public static void AddUnsupportedOSPlatform (List<AttributeWriter> attributes, AndroidSdkVersion since, CodeGenerationOptions opt)
-		{
-			// Here it makes sense to still write 'android15' because it will be missing in later versions like `android35`.
-			if (since > 0 && opt.CodeGenerationTarget == CodeGenerationTarget.XAJavaInterop1)
-				attributes.Add (new UnsupportedOSPlatformAttr (since));
-		}
-
 		public static void AddObsolete (List<AttributeWriter> attributes, string message, CodeGenerationOptions opt, bool forceDeprecate = false, bool isError = false, AndroidSdkVersion? deprecatedSince = null)
 		{
 			// Bail if we're not obsolete