Store JoinableTaskContext in TeamExplorerServiceHolder

No need to create a special JoinableTaskCollection and JoinableTaskFactory here.

Author: jcansdale

src/GitHub.Exports/Services/ITeamExplorerServiceHolder.cs

@@ -36,7 +36,7 @@ public interface ITeamExplorerServiceHolder
         /// <summary>
         /// A service for avoiding deadlocks and marshaling tasks onto the UI thread.
         /// </summary>
-        JoinableTaskFactory JoinableTaskFactory { get; }
+        JoinableTaskContext JoinableTaskContext { get; }
 
         IGitAwareItem HomeSection { get; }
     }

src/GitHub.TeamFoundation.14/Base/TeamExplorerServiceHolder.cs

@@ -23,12 +23,7 @@ public class TeamExplorerServiceHolder : ITeamExplorerServiceHolder
         public TeamExplorerServiceHolder(ITeamExplorerContext teamExplorerContext,
             [Import(AllowDefault = true)] JoinableTaskContext joinableTaskContext)
         {
-            joinableTaskContext = joinableTaskContext ?? ThreadHelper.JoinableTaskContext;
-
-            JoinableTaskCollection = joinableTaskContext.CreateCollection();
-            JoinableTaskCollection.DisplayName = nameof(TeamExplorerServiceHolder);
-            JoinableTaskFactory = joinableTaskContext.CreateFactory(JoinableTaskCollection);
-
+            JoinableTaskContext = joinableTaskContext ?? ThreadHelper.JoinableTaskContext;
             TeamExplorerContext = teamExplorerContext;
         }
 
@@ -82,8 +77,7 @@ ITeamExplorerPage PageService
             get { return ServiceProvider.GetServiceSafe<ITeamExplorerPage>(); }
         }
 
-        public JoinableTaskCollection JoinableTaskCollection { get; }
-        public JoinableTaskFactory JoinableTaskFactory { get; }
+        public JoinableTaskContext JoinableTaskContext { get; }
         public ITeamExplorerContext TeamExplorerContext { get; }
     }
 }

src/GitHub.VisualStudio.UI/Base/TeamExplorerItemBase.cs

@@ -87,9 +87,9 @@ void TeamExplorerContext_PropertyChanged(object sender, PropertyChangedEventArgs
 
         void UpdateRepoOnMainThread(LocalRepositoryModel repo)
         {
-            holder.JoinableTaskFactory.RunAsync(async () =>
+            holder.JoinableTaskContext.Factory.RunAsync(async () =>
             {
-                await holder.JoinableTaskFactory.SwitchToMainThreadAsync();
+                await holder.JoinableTaskContext.Factory.SwitchToMainThreadAsync();
                 UpdateRepo(repo);
             }).Task.Forget();
         }