Merge pull request #39532 from JoeRobich/is-packageservice-enabled

Check that PackageInstallerService is enabled before getting sources

src/Features/Core/Portable/AddImport/AbstractAddImportCodeFixProvider.cs

@@ -54,7 +54,7 @@ public sealed override async Task RegisterCodeFixesAsync(CodeFixContext context)
                 : null;
 
             var installerService = GetPackageInstallerService(document);
-            var packageSources = searchNuGetPackages && symbolSearchService != null && installerService != null
+            var packageSources = searchNuGetPackages && symbolSearchService != null && installerService?.IsEnabled(document.Project.Id) == true
                 ? installerService.GetPackageSources()
                 : ImmutableArray<PackageSource>.Empty;