Bump MSBuild from 17.11.4 to 17.12.6 (#313)

Author: jeffkl

Directory.Packages.props

@@ -2,8 +2,8 @@
 <Project xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
   <PropertyGroup>
     <ManagePackageVersionsCentrally>true</ManagePackageVersionsCentrally>
-    <MicrosoftBuildPackageVersion>17.11.4</MicrosoftBuildPackageVersion>
-    <MicrosoftBuildPackageVersion Condition="'$(TargetFramework)' == 'net6.0'">17.11.4</MicrosoftBuildPackageVersion>
+    <MicrosoftBuildPackageVersion>17.12.6</MicrosoftBuildPackageVersion>
+    <MicrosoftBuildPackageVersion Condition="'$(TargetFramework)' == 'net6.0' Or '$(TargetFramework)' == 'net8.0' ">17.11.4</MicrosoftBuildPackageVersion>
     <SystemTextJsonVersion>8.0.5</SystemTextJsonVersion>
     <SystemTextJsonVersion Condition="'$(TargetFramework)' == 'net6.0'">8.0.5</SystemTextJsonVersion>
   </PropertyGroup>

src/Microsoft.Build.Utilities.ProjectCreation/BuildManagerHost.cs

@@ -38,11 +38,24 @@ internal static class BuildManagerHost
         /// <param name="loggers">An <see cref="IEnumerable{T}" /> containing <see cref="ILogger" /> items to use.</param>
         /// <param name="buildRequestDataFlags">The <see cref="BuildRequestDataFlags" /> to use.</param>
         /// <returns>A <see cref="BuildResult" /> containing details about the result of the build.</returns>
-        public static BuildResult Build(string projectFullPath, string[] targets, IDictionary<string, string> globalProperties, IEnumerable<ILogger> loggers, BuildRequestDataFlags buildRequestDataFlags)
+        public static BuildResult Build(
+            string projectFullPath,
+            string[] targets,
+#if NET8_0
+            IDictionary<string, string> globalProperties,
+#else
+            IDictionary<string, string?> globalProperties,
+#endif
+            IEnumerable<ILogger> loggers,
+            BuildRequestDataFlags buildRequestDataFlags)
         {
             BuildRequestData buildRequestData = new BuildRequestData(
                 projectFullPath,
+#if NET8_0
                 globalProperties ?? new Dictionary<string, string>(),
+#else
+                globalProperties ?? new Dictionary<string, string?>(),
+#endif
                 toolsVersion: null,
                 targets ?? Array.Empty<string>(),
                 hostServices: null,

src/Microsoft.Build.Utilities.ProjectCreation/ProjectCreator.Build.cs

@@ -544,7 +544,12 @@ private void Restore(IDictionary<string, string>? globalProperties, BuildOutput
             Save();
 
             // IMPORTANT: Make a copy of the global properties here so as not to modify the ones passed in
-            Dictionary<string, string> restoreGlobalProperties = new Dictionary<string, string>(globalProperties ?? ProjectCollection.GlobalProperties);
+#if NET8_0
+            Dictionary<string, string> restoreGlobalProperties =
+#else
+            Dictionary<string, string?> restoreGlobalProperties =
+#endif
+                new(globalProperties ?? ProjectCollection.GlobalProperties);
 
             restoreGlobalProperties["ExcludeRestorePackageImports"] = "true";
             restoreGlobalProperties["MSBuildRestoreSessionId"] = Guid.NewGuid().ToString("D");