Merge pull request #16376 from heejaechang/defaultSessionOnUI

make sure we initialize TelemetryHelper from UI threads before we usi…

src/VisualStudio/Core/Def/Telemetry/RoslynTelemetrySetup.cs

 using System;
-using System.ComponentModel.Composition;
 using System.Diagnostics;
-using Microsoft.CodeAnalysis.Host;
 using Microsoft.CodeAnalysis.Internal.Log;
 using Microsoft.CodeAnalysis.Options;
+using Microsoft.Internal.VisualStudio.Shell;
 using Microsoft.Internal.VisualStudio.Shell.Interop;
 using Microsoft.VisualStudio.ComponentModelHost;
-using Microsoft.VisualStudio.LanguageServices;
-using Microsoft.VisualStudio.LanguageServices.Setup;
 
 namespace Microsoft.VisualStudio.LanguageServices.Telemetry
 {
@@ -18,6 +15,13 @@ public static void Initialize(IServiceProvider serviceProvider)
             var componentModel = (IComponentModel)serviceProvider.GetService(typeof(SComponentModel));
             var optionService = componentModel.GetService<IGlobalOptionService>();
 
+            // Fetch the session synchronously on the UI thread; if this doesn't happen before we try using this on
+            // the background thread then we will experience hangs like we see in this bug:
+            // https://devdiv.visualstudio.com/DefaultCollection/DevDiv/_workitems?_a=edit&id=190808 or
+            // https://devdiv.visualstudio.com/DevDiv/_workitems?id=296981&_a=edit
+            var unused1 = TelemetryHelper.TelemetryService;
+            var unused2 = TelemetryHelper.DefaultTelemetrySession;
+
             var telemetryService = serviceProvider.GetService(typeof(SVsTelemetryService)) as IVsTelemetryService;
             Logger.SetLogger(
                 AggregateLogger.Create(

src/VisualStudio/Core/Def/Telemetry/VSTelemetryActivityLogger.cs

@@ -30,11 +30,6 @@ public VSTelemetryActivityLogger(IVsTelemetryService service) : base(assertIsFor
         {
             _service = service;
             _pendingActivities = new ConcurrentDictionary<int, TelemetryActivity>(concurrencyLevel: 2, capacity: 10);
-
-            // Fetch the session synchronously on the UI thread; if this doesn't happen before we try using this on
-            // the background thread then we will experience hangs like we see in this bug:
-            // https://devdiv.visualstudio.com/DefaultCollection/DevDiv/_workitems?_a=edit&id=190808
-            var unused = TelemetryHelper.DefaultTelemetrySession;
         }
 
         public bool IsEnabled(FunctionId functionId)