Improve XA0141 warning

[jpobst]

.NET 9.0.100

The NuGet package information in the XA0141 warning seems helpful, but it doesn't appear to actually work.

Repro:

dotnet new android
dotnet add package Xamarin.GooglePlayServices.Vision.Face.Contour.Internal --version 116.1.0.19
dotnet build -c Release

results in:

warning XA0141: NuGet package '<unknown>' version '<unknown>' contains a shared library 'libface_detector_v2_jni.so' which is not correctly aligned. See https://developer.android.com/guide/practices/page-sizes for more details
warning XA0141: NuGet package '<unknown>' version '<unknown>' contains a shared library 'libface_detector_v2_jni.so' which is not correctly aligned. See https://developer.android.com/guide/practices/page-sizes for more details

We should:

• Either fix the NuGet information to be more accurate or remove it.
• Maybe add the arch information to the file name (arm64-v8a/libface_detector_v2_jni.so), as each package will likely contain many versions with the same file name.
• Rewrite the warning to be a little less scary, emphasizing this is a future problem, not necessarily something that needs to be fixed today. ("is not correctly aligned" sounds like the library is broken today)

An updated example:

warning XA0141: NuGet package 'Xamarin.GooglePlayServices.Vision.Face.Contour.Internal' version '116.1.0.19' contains a shared library 'arm64-v8a/libface_detector_v2_jni.so' which is not 16KB aligned. Google may require 16KB aligned libraries in the future. See https://developer.android.com/guide/practices/page-sizes for more details.

[grendello]

I think @dellis1972 looked into it sometime ago and determined that the information isn't available for transient packages. I'll see to adding arch information, but I can't do much about getting better nuget info. I'll leave that to @dellis1972 and @jonathanpeppers :)

[grendello]

Partial fix: #9547

[jonpryor]

This is going to require a fair bit of "plumbing" that I don't currently understand.

Working backwards:

• libface_detector_v2_jni.so comes from obj/Release/net9.0-android/lp/92/jl/jni/armeabi-v7a/libface_detector_v2_jni.so, obj/Release/net9.0-android/lp/76/jl/jni/armeabi-v7a/libface_detector_v2_jni.so
• as per obj/Release/net9.0-android/lp/map.cache:
  • obj/Release/net9.0-android/lp/92 is from playservicesvisionfacecontourinternal-16.1.0.aar
  • obj/Release/net9.0-android/lp/76 is from play-services-vision-face-contour-internal.aar
• Both playservicesvisionfacecontourinternal-16.1.0.aar and play-services-vision-face-contour-internal.aar are from @(XamarinBuildDownload) artifacts, e.g.

  11:04:44.957   1:7>Target "_XbdRestoreItems_playservicesvisionfacecontourinternal_16_1_0: (TargetId:147)" in file "$HOME/.nuget/packages/xamarin.googleplayservices.vision.face.contour.internal/116.1.0.19/buildTransitive/net8.0-android34.0/Xamarin.GooglePlayServices.Vision.Face.Contour.Internal.targets" from project "/Volumes/Xamarin-Work/tmp/gda-9544/gda-9544.csproj" (target "_XamarinBuildAddDownloadedItems" depends on it):
                     Added Item(s): 
                         XamarinBuildDownload=
                             playservicesvisionfacecontourinternal-16.1.0
                                     Kind=Uncompressed
                                     Sha256=
                                     ToFile=playservicesvisionfacecontourinternal-16.1.0.aar
                                     Url=https://dl.google.com/dl/android/maven2/com/google/android/gms/play-services-vision-face-contour-internal/16.1.0/play-services-vision-face-contour-internal-16.1.0.aar
  

• Ergo, play-services-vision-face-contour-internal-16.1.0.aar comes from the Xamarin.GooglePlayServices.Vision.Face.Contour.Internal NuGet package.

How do we provide enough information/metadata/etc. for <BuildApk/>, when given obj/Release/net9.0-android/lp/92/jl/jni/armeabi-v7a/libface_detector_v2_jni.so, that it can "work backwards" and determine that it comes from the Xamarin.GooglePlayServices.Vision.Face.Contour.Internal NuGet package?

[grendello]

Nuget information can be propagated to the .so ITaskItem from the _ReferencePath item, which has all the nuget info.

[jonpryor]

See also: #9559