…droid

Context: #21256 / 52a6f3e
Context: dotnet/android#10461
Context: dotnet/android#10457
Context: dotnet/android#10463

#21256 added support for building with .NET 10, and
one of the new features in .NET 10 is that Android has (very!)
preliminary preview support for [NativeAOT][0].

As building `SamplesApp.Skia.netcoremobile.csproj` with NativeAOT
takes a significant amount of time and disk space, we've decided to
introduce a new `Tests - Android+NativeAOT Skia` stage to build and
run these unit tests within an Android+NativeAOT environment.
To help reduce disk usage, after building the `.apk` we delete the
`obj` directory.

Update `android-run-skia-runtime-tests.sh` to always create
the `$(build.sourcesdirectory)/build/uitests-failure-results` path
before existing with an error, as failure to do so means that the
`PublishBuildArtifacts@1` YAML task fails:

	##[error]Publishing build artifacts failed with an error: Not found PathtoPublish: /agent/_work/1/s/build/uitests-failure-results

which in turn means subsequent `DownloadBuildArtifacts@0` /
**Download previous test runs failed tests** steps *also* always fail:

	##[error]Artifact uitests-android-nativeaot-failure-results not found for build 174635. Please ensure you have published artifacts in any previous phases of the current build.

Update `ApplicationData.GetRoamingFolder()` to explicitly create
`Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData)`.
(Apparently this isn't created by default under NativeAOT?)
This avoids a startup assertion:

	I NativeAotFromAndroid: App failed to initialize: System.IO.DirectoryNotFoundException: IO_PathNotFound_Path, /data/user/0/uno.platform.samplesapp.skia/files/.config/b63c4306-f361-42d0-bc1d-5be385a95c78.txt
	I NativeAotFromAndroid:    at System.IO.FileSystem.DeleteFile(String) + 0xe7
	I NativeAotFromAndroid:    at SamplesApp.App.<AssertApplicationData>g__AssertCanCreateFile|32_3(StorageFolder) + 0x10c
	I NativeAotFromAndroid:    at SamplesApp.App.AssertApplicationData() + 0xa5
	I NativeAotFromAndroid:    at SamplesApp.App..ctor() + 0x2a3
	I NativeAotFromAndroid:    at SamplesApp.Droid.Application.<>c.<.ctor>b__0_0() + 0x18
	I NativeAotFromAndroid:    at Microsoft.UI.Xaml.NativeApplication.<OnActivityStarted>b__7_0() + 0x12
	I NativeAotFromAndroid:    at Uno.UI.Runtime.Skia.Android.AndroidHost.<Run>g__CreateApp|2_10(ApplicationInitializationCallbackParams _) + 0xf
	I NativeAotFromAndroid:    at Microsoft.UI.Xaml.Application.StartPartial(ApplicationInitializationCallback callback) + 0xb5
	I NativeAotFromAndroid:    at Uno.UI.Runtime.Skia.Android.AndroidHost.Run() + 0x306

Enable NativeAOT builds by updating
`SamplesApp.Skia.netcoremobile.csproj` to set the [`$(PublishAot)`][1]
property to the `$(SkiaPublishAot)` MSBuild property.  This allows
us to build a single project for NativeAOT --
`SamplesApp.Skia.netcoremobile.csproj` -- *without* trying to build
every referenced project for NativeAOT, which is what happens if you
instead try `dotnet publish -p:PublishAot=true …`:

	% dotnet build -c Release -p:PublishAot=true src/SamplesApp/SamplesApp.Skia.netcoremobile/SamplesApp.Skia.netcoremobile.csproj -bl
	…
	…/Microsoft.NET.Sdk.FrameworkReferenceResolution.targets(121,5): error NETSDK1207: Ahead-of-time compilation is not supported for the target framework.

	% dotnet publish src/SamplesApp/SamplesApp.Skia.netcoremobile/SamplesApp.Skia.netcoremobile.csproj \
	  -c Release -r android-x64 -f net10.0-android -p:UnoTargetFrameworkOverride=net10.0-android -p:SkiaPublishAot=true -bl
	# succeeds… after 15 minutes…

This also requires updating `$(NoWarn)` to ignore the hundreds of
IL trimmer warnings.  We're just trying to see where things stand for now.

Additionally, we need to publish with `-r android-x64` in order to
avoid the build error:

	…/Microsoft.NETCore.Native.Publish.targets(92,5): error MSB3030: Could not copy the file "bin/Release/net10.0-android/native/SamplesApp.so" because it was not found.

Because it's `bin/Release/net10.0-android/android-{arm64,x64}/native/SamplesApp.so`!

Oddly, using `-r android-x64` still results in *both* ABIs being
included, which appears to be a unoplatform/uno "bug":

	% unzip -l src/SamplesApp/SamplesApp.Skia.netcoremobile/bin/Release/net10.0-android/android-x64/publish/uno.platform.samplesapp.skia-Signed.apk | grep SamplesApp.so
	763563120  08-28-2025 19:47   lib/x86_64/libSamplesApp.so
	757982224  08-28-2025 19:48   lib/arm64-v8a/libSamplesApp.so

The need for `-r android-x64` may be related to dotnet/android#10457.

Finally, .NET Crypto support isn't propertly initialized in
Android+NativeAOT apps in .NET 10 RC1; see dotnet/android#10463.
This may be fixed in dotnet/android#10461, but in the meantime we can
manually call `AndroidCryptoNative_InitLibraryOnLoad()` so that
methods such as `SHA1.Create()` won't throw.

Note: Do *not* make Release-config apps [Debuggable][2] under
.NET 10 Preview 7 or earlier; you will run into
[dotnet/java-interop@90ac202e][3].

[0]: https://learn.microsoft.com/en-us/dotnet/core/deploying/native-aot/
[1]: https://learn.microsoft.com/en-us/dotnet/core/deploying/native-aot/?tabs=windows%2Cnet8#publish-native-aot-using-the-cli
[2]: https://developer.android.com/guide/topics/manifest/application-element#debug
[3]: dotnet/java-interop@90ac202