[Java.Interop.Tools.TypeNameMappings] introduce project for net8.0 (#1199)

Context: dotnet/android#8751
Context: https://devdiv.visualstudio.com/DevDiv/_build/results?buildId=9137456&view=logs&j=96fd57f5-f69e-53c7-3d47-f67e6cf9b93e&s=1afc3bfe-122c-538b-e9ad-2a86c2efcfef&t=38f83f46-bc21-5edd-1614-e44f20babf10&l=29658
Context: 67c079c
Context: 56b7eeb

dotnet/android#8751 has a random build failure:

	"Xamarin.Android.sln" (default target) (1:2) ->
	"src/Xamarin.Android.Build.Tasks/Xamarin.Android.Build.Tasks.csproj" (default target) (28:9) ->
	(CoreCompile target) ->
	    src/Xamarin.Android.Build.Tasks/Utilities/MamJsonParser.cs(92,43): error CS0122: 'NotNullWhenAttribute' is inaccessible due to its protection level [src/Xamarin.Android.Build.Tasks/Xamarin.Android.Build.Tasks.csproj]
	    src/Xamarin.Android.Build.Tasks/Utilities/MamJsonParser.cs(92,81): error CS0122: 'NotNullWhenAttribute' is inaccessible due to its protection level [src/Xamarin.Android.Build.Tasks/Xamarin.Android.Build.Tasks.csproj]
	    src/Xamarin.Android.Build.Tasks/Utilities/MavenExtensions.cs(26,32): error CS0122: 'NotNullWhenAttribute' is inaccessible due to its protection level [src/Xamarin.Android.Build.Tasks/Xamarin.Android.Build.Tasks.csproj]

It happens some percentage of the time…

Similar to 67c079c, the cause is that commit 56b7eeb updated
`Java.Interop.Tools.JavaCallableWrappers.csproj` to multitarget both
netstandard2.0 and net8.0, and on some builds the
`Java.Interop.Tools.JavaCallableWrappers.dll` used by
`Xamarin.Android.Build.Tasks.csproj` is the net8.0 build, *not* the
netstandard2.0 build.

To fix this:

  * Don't build `Java.Interop.Tools.JavaCallableWrappers.csproj` for
    `net8.0` anymore; remove net8.0 from `$(TargetFrameworks)`.

  * Introduce a new `Java.Interop.Tools.TypeNameMappings.csproj`
    project which builds the source code within
    `Java.Interop.Tools.JavaCallableWrappers.csproj` for net8.0.
    The resulting assembly is not shipped or used.  It can check
    trimmer warnings, though.

This partially reverts 67c079c and 56b7eeb.

Author: jonathanpeppers

Java.Interop.sln

@@ -115,6 +115,10 @@ Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Java.Interop.Tools.Expressi
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Hello-NativeAOTFromJNI", "samples\Hello-NativeAOTFromJNI\Hello-NativeAOTFromJNI.csproj", "{8DB3842B-73D7-491C-96F9-EBC863E2C917}"
 EndProject
+Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "src", "src", "{40B3CE2F-B8DE-45CD-A43A-0F1A89BDB803}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Java.Interop.Tools.TypeNameMappings", "src\Java.Interop.Tools.TypeNameMappings\Java.Interop.Tools.TypeNameMappings.csproj", "{C2AF6ACF-04F6-4B41-95EA-97A372C075F9}"
+EndProject
 Global
 	GlobalSection(SharedMSBuildProjectFiles) = preSolution
 		src\Java.Interop.NamingCustomAttributes\Java.Interop.NamingCustomAttributes.projitems*{58b564a1-570d-4da2-b02d-25bddb1a9f4f}*SharedItemsImports = 5
@@ -326,6 +330,10 @@ Global
 		{8DB3842B-73D7-491C-96F9-EBC863E2C917}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{8DB3842B-73D7-491C-96F9-EBC863E2C917}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{8DB3842B-73D7-491C-96F9-EBC863E2C917}.Release|Any CPU.Build.0 = Release|Any CPU
+		{C2AF6ACF-04F6-4B41-95EA-97A372C075F9}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{C2AF6ACF-04F6-4B41-95EA-97A372C075F9}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{C2AF6ACF-04F6-4B41-95EA-97A372C075F9}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{C2AF6ACF-04F6-4B41-95EA-97A372C075F9}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
@@ -381,6 +389,7 @@ Global
 		{1A0262FE-3CDB-4AF2-AAD8-65C59524FE8A} = {0998E45F-8BCE-4791-A944-962CD54E2D80}
 		{211BAA88-66B1-41B2-88B2-530DBD8DF702} = {271C9F30-F679-4793-942B-0D9527CB3E2F}
 		{8DB3842B-73D7-491C-96F9-EBC863E2C917} = {D5A93398-AEB1-49F3-89DC-3904A47DB0C7}
+		{C2AF6ACF-04F6-4B41-95EA-97A372C075F9} = {40B3CE2F-B8DE-45CD-A43A-0F1A89BDB803}
 	EndGlobalSection
 	GlobalSection(ExtensibilityGlobals) = postSolution
 		SolutionGuid = {29204E0C-382A-49A0-A814-AD7FBF9774A5}

src/Java.Interop.Tools.JavaCallableWrappers/Java.Interop.Tools.JavaCallableWrappers.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFrameworks>netstandard2.0;$(DotNetTargetFramework)</TargetFrameworks>
+    <TargetFramework>netstandard2.0</TargetFramework>
     <LangVersion>11.0</LangVersion>
     <Nullable>enable</Nullable>
     <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
@@ -13,24 +13,17 @@
 
   <Import Project="..\..\TargetFrameworkDependentValues.props" />
 
-  <!-- Only use $(ToolOutputFullPath) for netstandard2.0 -->
-  <PropertyGroup Condition=" '$(TargetFramework)' == 'netstandard2.0' ">
+  <PropertyGroup>
     <OutputPath>$(ToolOutputFullPath)</OutputPath>
   </PropertyGroup>
 
-  <PropertyGroup Condition=" '$(TargetFramework)' != 'netstandard2.0' ">
-    <IsTrimmable>true</IsTrimmable>
-    <EnableSingleFileAnalyzer>true</EnableSingleFileAnalyzer>
-    <EnableAotAnalyzer>true</EnableAotAnalyzer>
-  </PropertyGroup>
-
   <Import Project="..\..\build-tools\scripts\cecil.projitems" />
 
   <ItemGroup>
     <Compile Include="..\Java.Interop.Tools.TypeNameMappings\Java.Interop.Tools.TypeNameMappings\JavaNativeTypeManager.cs">
       <Link>JavaNativeTypeManager.cs</Link>
     </Compile>
-    <Compile Include="..\utils\NullableAttributes.cs" Condition=" '$(TargetFramework)' == 'netstandard2.0' ">
+    <Compile Include="..\utils\NullableAttributes.cs">
       <Link>NullableAttributes.cs</Link>
     </Compile>
   </ItemGroup>

src/Java.Interop.Tools.TypeNameMappings/Java.Interop.Tools.TypeNameMappings.csproj

@@ -0,0 +1,29 @@
+<Project Sdk="Microsoft.NET.Sdk">
+  <PropertyGroup>
+    <TargetFramework>$(DotNetTargetFramework)</TargetFramework>
+    <Nullable>enable</Nullable>
+    <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
+    <IsTrimmable>true</IsTrimmable>
+    <EnableSingleFileAnalyzer>true</EnableSingleFileAnalyzer>
+    <EnableAotAnalyzer>true</EnableAotAnalyzer>
+    <DefineConstants>$(DefineConstants);JCW_ONLY_TYPE_NAMES;HAVE_CECIL</DefineConstants>
+  </PropertyGroup>
+
+  <Import Project="..\..\TargetFrameworkDependentValues.props" />
+  <Import Project="..\..\build-tools\scripts\cecil.projitems" />
+
+  <ItemGroup>
+    <ProjectReference Include="..\Java.Interop.Localization\Java.Interop.Localization.csproj" />
+    <ProjectReference Include="..\Java.Interop.Tools.Cecil\Java.Interop.Tools.Cecil.csproj" />
+    <ProjectReference Include="..\Java.Interop.Tools.Diagnostics\Java.Interop.Tools.Diagnostics.csproj" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <Compile Include="..\Java.Interop.Tools.JavaCallableWrappers\Java.Interop.Tools.JavaCallableWrappers\Crc64.cs" />
+    <Compile Include="..\Java.Interop.Tools.JavaCallableWrappers\Java.Interop.Tools.JavaCallableWrappers\Crc64.Table.cs" />
+    <Compile Include="..\Java.Interop.Tools.JavaCallableWrappers\Java.Interop.Tools.JavaCallableWrappers\Crc64Helper.cs" />
+  </ItemGroup>
+
+  <Import Project="..\Java.Interop.NamingCustomAttributes\Java.Interop.NamingCustomAttributes.projitems" Label="Shared" Condition="Exists('..\Java.Interop.NamingCustomAttributes\Java.Interop.NamingCustomAttributes.projitems')" />
+
+</Project>