Bindings of `abstract` methods should be `[Obsolete]` if Java method is `@Deprecated`

[jonpryor]

Context: #968
Context: #968 (comment)

PR #968 "uncovered" that if you have a Java abstract method which is deprecated:

public abstract class Example {
 @Deprecated
 public abstract void m();
}

then the C# binding is not [Obsolete], and the *Invoker override is [Obsolete]:

// Binding
public abstract partial class Example : Java.Lang.Object {
 [Register (…)]
 public abstract void M();
}

internal partial class ExampleInvoker : Example {
 [Obsolete]
 public override void M() => …
}

This state of affairs results in a CS0809 warning:

Error CS0809: Obsolete member 'ExampleInvoker.M()' overrides non-obsolete member 'Example.M()'

PR #968 fixed this warning for CodeGenerationTarget.JavaInterop1.

Should this also be done for CodeGenerationTarget.XAJavaInterop1?