[Xamarin.Android.Build.Tasks] fix Inputs for _Generate*Java* targ…

…ets (dotnet#9174)

Fixes: dotnet#8967
Context: dotnet#9001

You can cause a build error in .NET 8 by doing:

* Start an x86 or x86_64 emulator
* `dotnet build -t:Run`
* Close the emulator, attach an arm or arm64 device
* `dotnet build -t:Run`

Emits the error:

    Xamarin.Android.Common.targets(2063,3): error XA3006: Could not compile native assembly file: typemaps.x86_64.ll
    stderr | C:\Program Files\dotnet\packs\Microsoft.Android.Sdk.Windows\34.0.113\tools\binutils\bin\llc.exe: error: C:\Program Files\dotnet\packs\Microsoft.Android.Sdk.Windows\34.0.113\tools\binutils\bin\llc.exe: typemaps.x86_64.ll: error: Could not open input file: no such file or directory

This works fine in Visual Studio, but not at the command-line.

The underlying problem is due to `_GeneratePackageManagerJava` target
running, while the `_GenerateJavaStubs` target *did not*:

    Skipping target "_GenerateJavaStubs" because all output files are up-to-date with respect to the input files.
    ...
    Input file "obj\Debug\net8.0-android\resolvedassemblies.hash" is newer than output file "obj\Debug\net8.0-android\stamp\_GeneratePackageManagerJava.stamp".

These two targets should almost always run together, so we should
ensure that they do.

This problem also doesn't happen .NET 9, as both targets are
invalidated for a different reason:

    Target Name=_LinkAssembliesNoShrink Project=UnnamedProject.csproj
    Building target "_LinkAssembliesNoShrink" completely.
    Output file "obj\Debug\android\assets\x86_64\UnnamedProject.dll" does not exist.

Since, we build per-RID in .NET 9, `obj\Debug\android\assets\x86_64\UnnamedProject.dll`
has an `x86_64` in the path, which is not present in the .NET 8 build.

Reviewing the two sets of `Inputs`:

    <Target Name="_GenerateJavaStubs"
        ...
        Inputs="@(_AndroidMSBuildAllProjects);@(_ResolvedUserMonoAndroidAssemblies);$(_AndroidManifestAbs);$(_AndroidBuildPropertiesCache);@(AndroidEnvironment);@(LibraryEnvironments)"
    ...
    <Target Name="_GeneratePackageManagerJava"
        ...
        Inputs="@(_AndroidMSBuildAllProjects);$(_ResolvedUserAssembliesHashFile);$(MSBuildProjectFile);$(_AndroidBuildPropertiesCache);@(AndroidEnvironment);@(LibraryEnvironments)"

Let's align them more closely by:

* Track assembly changes in the exact same way:

    $(_ResolvedUserAssembliesHashFile);@(_ResolvedUserMonoAndroidAssemblies);

This way if an assembly is added, removed, or timestamp changed: both
targets are in sync.

* Don't track `$(MSBuildProjectFile)`, this should already be in
  `@(_AndroidMSBuildAllProjects)`.

With this change in place manually, I'm not able to reproduce the
problem any longer.

PR dotnet#9001 may also have fixed this issue, but it could cause targets to
run on every incremental build -- a performance issue.

src/Xamarin.Android.Build.Tasks/Tests/Xamarin.Android.Build.Tests/BuildTest.cs

@@ -1655,5 +1655,36 @@ public void SimilarAndroidXAssemblyNames ([Values(true, false)] bool publishTrim
 			using var builder = CreateApkBuilder ();
 			Assert.IsTrue (builder.Build (proj), "Build should have succeeded.");
 		}
+
+		[Test]
+		public void IncrementalBuildDifferentDevice()
+		{
+			var proj = new XamarinAndroidApplicationProject {
+				Imports = {
+					new Import (() => "MockPrimaryCpuAbi.targets") {
+						TextContent = () =>
+"""
+<Project>
+	<!-- This target "mocks" what _GetPrimaryCpuAbi does -->
+	<Target Name="_MockPrimaryCpuAbi" BeforeTargets="_CreatePropertiesCache">
+		<PropertyGroup>
+			<RuntimeIdentifier>$(_SingleRID)</RuntimeIdentifier>
+			<RuntimeIdentifiers></RuntimeIdentifiers>
+			<AndroidSupportedAbis>$(_SingleABI)</AndroidSupportedAbis>
+		</PropertyGroup>
+	</Target>
+</Project>
+"""
+					},
+				},
+			};
+			using var builder = CreateApkBuilder ();
+			builder.Target = "Build";
+			builder.BuildingInsideVisualStudio = false;
+			Assert.IsTrue (builder.Build (proj, parameters: [ "_SingleRID=android-arm64", "_SingleABI=arm64-v8a" ]),
+				"first build should have succeeded.");
+			Assert.IsTrue (builder.Build (proj, parameters: [ "_SingleRID=android-x64", "_SingleABI=x86_64" ], doNotCleanupOnUpdate: true),
+				"second build should have succeeded.");
+		}
 	}
 }

src/Xamarin.Android.Build.Tasks/Xamarin.Android.Common.targets

@@ -1444,7 +1444,7 @@ because xbuild doesn't support framework reference assemblies.
 
 <Target Name="_GenerateJavaStubs"
     DependsOnTargets="$(_GenerateJavaStubsDependsOnTargets);$(BeforeGenerateAndroidManifest)"
-    Inputs="@(_AndroidMSBuildAllProjects);@(_ResolvedUserMonoAndroidAssemblies);$(_AndroidManifestAbs);$(_AndroidBuildPropertiesCache);@(AndroidEnvironment);@(LibraryEnvironments)"
+    Inputs="@(_AndroidMSBuildAllProjects);$(_ResolvedUserAssembliesHashFile);@(_ResolvedUserMonoAndroidAssemblies);$(_AndroidManifestAbs);$(_AndroidBuildPropertiesCache);@(AndroidEnvironment);@(LibraryEnvironments)"
     Outputs="$(_AndroidStampDirectory)_GenerateJavaStubs.stamp">
 
   <PropertyGroup>
@@ -1691,7 +1691,7 @@ because xbuild doesn't support framework reference assemblies.
 
 <Target Name="_GeneratePackageManagerJava"
   DependsOnTargets="$(_GeneratePackageManagerJavaDependsOn)"
-  Inputs="@(_AndroidMSBuildAllProjects);$(_ResolvedUserAssembliesHashFile);$(MSBuildProjectFile);$(_AndroidBuildPropertiesCache);@(AndroidEnvironment);@(LibraryEnvironments)"
+  Inputs="@(_AndroidMSBuildAllProjects);$(_ResolvedUserAssembliesHashFile);@(_ResolvedUserMonoAndroidAssemblies);$(_AndroidBuildPropertiesCache);@(AndroidEnvironment);@(LibraryEnvironments)"
   Outputs="$(_AndroidStampDirectory)_GeneratePackageManagerJava.stamp">
   <!-- Create java needed for Mono runtime -->
   <GeneratePackageManagerJava