[darc] track previous .NET Android manifests

[jonathanpeppers]

Context: dotnet/maui#28663

Previously we've been tracking:

<!-- Previous .NET Android version -->
<Dependency Name="Microsoft.Android.Sdk.Windows" Version="35.0.61">
  <Uri>https://github.com/dotnet/android</Uri>
  <Sha>e7876a4f92d894b40c191a24c2b74f06d4bf4573</Sha>
</Dependency>

And then for .NET 8, we just manually updated the
$(AndroidNet8PreviousVersion) property.

This makes it difficult for other repositories to know about the required NuGet feeds:

<!--Begin: Package sources managed by Dependency Flow automation. Do not edit the sources below.-->
<!--  Begin: Package sources from dotnet-android -->
<add key="darc-pub-dotnet-android-82d8938" value="https://pkgs.dev.azure.com/dnceng/public/_packaging/darc-pub-dotnet-android-82d8938c/nuget/v3/index.json" />
<add key="darc-pub-dotnet-android-e7876a4" value="https://pkgs.dev.azure.com/dnceng/public/_packaging/darc-pub-dotnet-android-e7876a4f/nuget/v3/index.json" />
<!--  End: Package sources from dotnet-android -->

In dotnet/maui or dotnet/performance, they would need to look at dotnet/android/main's NuGet.config to even figure out what is missing here:

Workload installation failed: One or more errors occurred. (Version 35.0.61 of package microsoft.android.sdk.windows is not found in NuGet feeds

To solve this, we can track:

<!-- Previous .NET Android version(s) -->
<Dependency Name="Microsoft.NET.Sdk.Android.Manifest-9.0.100" Version="35.0.61">
  <Uri>https://github.com/dotnet/android</Uri>
  <Sha>e7876a4f92d894b40c191a24c2b74f06d4bf4573</Sha>
</Dependency>
<Dependency Name="Microsoft.NET.Sdk.Android.Manifest-8.0.100" Version="34.0.154">
  <Uri>https://github.com/dotnet/android</Uri>
  <Sha>82d8938cf80f6d5fa6c28529ddfbdb753d805ab4</Sha>
</Dependency>

Then consuming repositories could track with
CoherentParentDependency="Microsoft.Android.Sdk.Windows":

<Dependency Name="Microsoft.Android.Sdk.Windows" Version="36.0.0-preview.3.11">
  <Uri>https://github.com/dotnet/android</Uri>
  <Sha>e71524ac874e90d9879661cafe230d8e99ba9cec</Sha>
</Dependency>
<Dependency Name="Microsoft.NET.Sdk.Android.Manifest-9.0.100" Version="35.0.61" CoherentParentDependency="Microsoft.Android.Sdk.Windows">
  <Uri>https://github.com/dotnet/android</Uri>
  <Sha>e7876a4f92d894b40c191a24c2b74f06d4bf4573</Sha>
</Dependency>
<Dependency Name="Microsoft.NET.Sdk.Android.Manifest-8.0.100" Version="34.0.154" CoherentParentDependency="Microsoft.Android.Sdk.Windows">
  <Uri>https://github.com/dotnet/android</Uri>
  <Sha>82d8938cf80f6d5fa6c28529ddfbdb753d805ab4</Sha>
</Dependency>

Once this change is merged, we would update eng/Version.Details.xml in consuming repositories. Afterwards, Maestro should be able to manage the feeds automatically.

[matouskozak]

fyi: @LoopedBard3 for dotnet/performance repo.

[pjcollins]

Do we have an idea of how many .NET 10 previews we plan to support .NET 8 targeting for? This is easy enough to revert whenever we drop that support either way, and should hopefully make dependency updating easier in general

[jonathanpeppers]

We will probably remove this entry around May, and remove this from the workload manifest at the same time:

android/src/Xamarin.Android.Build.Tasks/Microsoft.NET.Sdk.Android/WorkloadManifest.in.json

Lines 24 to 33 in e347cd3

	"android-net8": {
	"description": ".NET SDK Workload for building .NET 8 Android applications.",
	"packs": [ "Microsoft.Android.Sdk.net8" ],
	"platforms": [ "win-x64", "win-arm64", "linux-x64", "linux-arm64", "osx-x64", "osx-arm64" ],
	"extends" : [
	"android",
	"microsoft-net-runtime-android-net8",
	"microsoft-net-runtime-android-aot-net8"
	]
	}