Remove ApplyPreserveAttribute, warn when PreserveAttribute is referenced in assembly

[jtschuster]

PreserveAttribute has been obsolete for some time, so the functionality of the trimmer step which marks the types based on the can be removed. Instead, we can warn if we see any references to the type within an assembly.

Context: dotnet/runtime#107211

[jonathanpeppers]

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[jonathanpeppers]

Oh, maybe you forgot to commit 1 file.

If this is for .NET 11, I think we could also put error:true here:

android/src/Mono.Android/Android.Runtime/PreserveAttribute.cs

Line 35 in 68f1238

[Obsolete ("Please use [System.Diagnostics.CodeAnalysis.DynamicDependencyAttribute]")]

It has been marked [Obsolete] a long time.

[jtschuster]

Ah, forgot to re-add the file after renaming it.

[jtschuster]

It seems like adding the error=true causes and API compat issue and we'll need to add [Obsolete] to the definition in Java.Interop?

[jonathanpeppers]

I think the one in java-interop is just for tests:

• https://github.com/dotnet/java-interop/blob/main/tests/generator-Tests/SupportFiles/PreserveAttribute.cs

Or did you find it when viewing the assembly in ILSpy?

[jtschuster]

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[jonathanpeppers]

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[jonathanpeppers]

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[jonathanpeppers]

We can look how to fix this later:

       (_CheckApiCompatibility target) -> 
         /Users/builder/azdo/_work/3/s/android/src/Mono.Android/Mono.Android.targets(216,5): error : CompatApi command: dotnet "/Users/builder/.nuget/packages/microsoft.dotnet.apicompat/7.0.0-beta.22103.1/tools/net472/../netcoreapp3.1/Microsoft.DotNet.ApiCompat.dll" "/Users/builder/azdo/_work/3/s/android/tests/api-compatibility/reference/net10.0/Mono.Android.dll" -i "/Users/builder/azdo/_work/3/s/android/bin/Release/lib/xamarin.android/xbuild-frameworks/Microsoft.Android/36" --allow-default-interface-methods --baseline "/Users/builder/azdo/_work/3/s/android/tests/api-compatibility/acceptable-breakages-vReference-net10.0.txt" --validate-baseline --exclude-attributes "/Users/builder/azdo/_work/3/s/android/tests/api-compatibility/api-compat-exclude-attributes.txt"  [/Users/builder/azdo/_work/3/s/android/src/Mono.Android/Mono.Android.csproj::TargetFramework=net10.0]
       /Users/builder/azdo/_work/3/s/android/src/Mono.Android/Mono.Android.targets(216,5): error : CheckApiCompatibility found nonacceptable Api breakages for ApiLevel: v16.0. [/Users/builder/azdo/_work/3/s/android/src/Mono.Android/Mono.Android.csproj::TargetFramework=net10.0]
       /Users/builder/azdo/_work/3/s/android/src/Mono.Android/Mono.Android.targets(216,5): error : Compat issues with assembly Mono.Android: [/Users/builder/azdo/_work/3/s/android/src/Mono.Android/Mono.Android.csproj::TargetFramework=net10.0]
       /Users/builder/azdo/_work/3/s/android/src/Mono.Android/Mono.Android.targets(216,5): error : CannotRemoveAttribute : Attribute 'System.ObsoleteAttribute' exists on 'Android.Runtime.PreserveAttribute' in the contract but not the implementation. [/Users/builder/azdo/_work/3/s/android/src/Mono.Android/Mono.Android.csproj::TargetFramework=net10.0]
       /Users/builder/azdo/_work/3/s/android/src/Mono.Android/Mono.Android.targets(216,5): error : Total Issues: 1 [/Users/builder/azdo/_work/3/s/android/src/Mono.Android/Mono.Android.csproj::TargetFramework=net10.0]

I think there is just a text file to update, so it can see the attribute changed.

[jtschuster]

/azp run

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[grendello]

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[jonathanpeppers]

Going to hold this until we've branched and main is .NET 11.

I'll come back to this and merge then. 👍