Simplify Roslyn assembly resolution logic

Author: Sergio0694

CommunityToolkit.Mvvm/CommunityToolkit.Mvvm.targets

@@ -12,30 +12,14 @@
           AfterTargets="ResolvePackageDependenciesForBuild;ResolveNuGetPackageAssets"
           DependsOnTargets="_MVVMToolkitGatherAnalyzers">
 
-    <PropertyGroup>
-      
-      <!-- If CSharpCoreTargetsPath is not empty, the Roslyn path is the directory name from there -->
-      <RoslynDirectoryName Condition="$(CSharpCoreTargetsPath) != ''">$([System.IO.Path]::GetDirectoryName($(CSharpCoreTargetsPath))</RoslynDirectoryName>
-      
-      <!-- Otherwise, fallback to $(MSBuildBinPath)\Roslyn\ -->
-      <RoslynDirectoryName Condition="$(RoslynDirectoryName) == ''">$([System.IO.Path]::Combine(`$(MSBuildBinPath)`,`Roslyn`))</RoslynDirectoryName>
-      
-      <!-- Actually check that Microsoft.Build.Tasks.CodeAnalysis.dll exists at the resolved location.
-           If it doesn't (eg. if the consuming project is a .wapproj project), remove the analyzer.
-           In that case, the warning will also not be emitted, as there are no C# files to compile anyway. -->
-      <RoslynAssemblyPath>$([System.IO.Path]::Combine(`$(RoslynDirectoryName)`,`Microsoft.Build.Tasks.CodeAnalysis.dll`))</RoslynAssemblyPath>
-      <IsRoslynAssemblyPresent Condition="$([System.IO.File]::Exists(`$(RoslynAssemblyPath)`)">true</IsRoslynAssemblyPresent>
-      <IsRoslynAssemblyPresent Condition="$(IsRoslynAssemblyPresent) == ''">false</IsRoslynAssemblyPresent>
-    </PropertyGroup>
-
     <Choose>
-      <When Condition="$(IsRoslynAssemblyPresent) == 'true'">
+      <When Condition="$(CSharpCoreTargetsPath) != ''">
 
         <!-- Use the CSharpCoreTargetsPath property to find the version of the compiler we are using. This is the same mechanism
              MSBuild uses to find the compiler. We could check the assembly version for any compiler assembly (since they all have
              the same version) but Microsoft.Build.Tasks.CodeAnalysis.dll is where MSBuild loads the compiler tasks from so if
              someone is getting creative with msbuild tasks/targets this is the "most correct" assembly to check. -->
-        <GetAssemblyIdentity AssemblyFiles="$(RoslynAssemblyPath)">
+        <GetAssemblyIdentity AssemblyFiles="$([System.IO.Path]::Combine(`$([System.IO.Path]::GetDirectoryName($(CSharpCoreTargetsPath)))`,`Microsoft.Build.Tasks.CodeAnalysis.dll`))">
           <Output TaskParameter="Assemblies" ItemName="CurrentCompilerAssemblyIdentity"/>
         </GetAssemblyIdentity>