Cache MEF catalog in servicehub process (#78122)

Cache the MEF catalog created in the roslyn code analysis process.

On my dev machine, the creation of the MEF catalog in our CA process takes about 500 ms. With this change, runs that were able to load from the cache saw that time reduced to about 150 ms.

The high-level change here is to piggy back on the work that Joey did a while back to add MEF catalog caching to our VSCode language server. This PR just moves that code down to a layer where our service hub code can reference, and generalized it a bit to fit into what the service hub code can provide.

One slight additional change in this PR was to add a new remote service to handle passing over the proper location to store the mef cache. I didn't feel comfortable fitting this into the previous first message sent across (IRemoteProcessTelemetryService), so I created IRemoteInitializationService to better fit what I wanted. This led to creating a separate type to handle the export provider creation (RemoteExportProvider) instead of tying this up into RemoteWorkspaceManager.

Author: ToddGrun

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);
     }
 }