Cache MEF catalog in servicehub process

eng/targets/Services.props

@@ -33,6 +33,7 @@
     <ServiceHubService Include="Microsoft.VisualStudio.LanguageServices.MissingImportDiscovery" ClassName="Microsoft.CodeAnalysis.Remote.RemoteMissingImportDiscoveryService+Factory" />
     <ServiceHubService Include="Microsoft.VisualStudio.LanguageServices.NavigateToSearch" ClassName="Microsoft.CodeAnalysis.Remote.RemoteNavigateToSearchService+Factory" />
     <ServiceHubService Include="Microsoft.VisualStudio.LanguageServices.NavigationBarItem" ClassName="Microsoft.CodeAnalysis.Remote.RemoteNavigationBarItemService+Factory" />
+    <ServiceHubService Include="Microsoft.VisualStudio.LanguageServices.Initialization" ClassName="Microsoft.CodeAnalysis.Remote.RemoteInitializationService+Factory" />
     <ServiceHubService Include="Microsoft.VisualStudio.LanguageServices.ProcessTelemetry" ClassName="Microsoft.CodeAnalysis.Remote.RemoteProcessTelemetryService+Factory" />
     <ServiceHubService Include="Microsoft.VisualStudio.LanguageServices.ProjectTelemetry" ClassName="Microsoft.CodeAnalysis.Remote.RemoteProjectTelemetryService+Factory" />
     <ServiceHubService Include="Microsoft.VisualStudio.LanguageServices.RelatedDocuments" ClassName="Microsoft.CodeAnalysis.Remote.RemoteRelatedDocumentsService+Factory" />

src/CodeStyle/Core/CodeFixes/Host/Mef/CodeStyleHostLanguageServices.cs

@@ -49,7 +49,7 @@ private static ImmutableArray<Assembly> CreateAssemblies(string languageName)
             }
 
             return MefHostServices.DefaultAssemblies.Concat(
-                MefHostServicesHelpers.LoadNearbyAssemblies(assemblyNames));
+                MefHostServicesHelpers.LoadNearbyAssemblies(assemblyNames.ToImmutableAndClear()));
         }
 
         IEnumerable<Lazy<TExtension>> IMefHostExportProvider.GetExports<TExtension>()

src/LanguageServer/Microsoft.CodeAnalysis.LanguageServer.UnitTests/ExportProviderBuilderTests.cs

@@ -148,15 +148,15 @@ public ImportType(ExportedType t) { }
 
     private async Task AssertCacheWriteWasAttemptedAsync()
     {
-        var cacheWriteTask = ExportProviderBuilder.TestAccessor.GetCacheWriteTask();
+        var cacheWriteTask = LanguageServerExportProviderBuilder.TestAccessor.GetCacheWriteTask();
         Assert.NotNull(cacheWriteTask);
 
         await cacheWriteTask;
     }
 
     private void AssertNoCacheWriteWasAttempted()
     {
-        var cacheWriteTask2 = ExportProviderBuilder.TestAccessor.GetCacheWriteTask();
+        var cacheWriteTask2 = LanguageServerExportProviderBuilder.TestAccessor.GetCacheWriteTask();
         Assert.Null(cacheWriteTask2);
     }
 

src/LanguageServer/Microsoft.CodeAnalysis.LanguageServer.UnitTests/Utilities/LanguageServerTestComposition.cs

@@ -33,6 +33,7 @@ public static Task<ExportProvider> CreateExportProviderAsync(
             UseStdIo: false);
         var extensionManager = ExtensionAssemblyManager.Create(serverConfiguration, loggerFactory);
         assemblyLoader = new CustomExportAssemblyLoader(extensionManager, loggerFactory);
-        return ExportProviderBuilder.CreateExportProviderAsync(extensionManager, assemblyLoader, devKitDependencyPath, cacheDirectory, loggerFactory);
+
+        return LanguageServerExportProviderBuilder.CreateExportProviderAsync(extensionManager, assemblyLoader, devKitDependencyPath, cacheDirectory, loggerFactory, CancellationToken.None);
     }
 }