Lock VSGitExt.RefreshActiveRepositories

Wait on a lock in `VSGitExt.RefreshActiveRepositories` so that `ActiveRepositoriesChanged` notifications are raised in the correct order.

Fixes #1493

Author: grokys

src/GitHub.TeamFoundation.14/Services/VSGitExt.cs

@@ -24,6 +24,7 @@ public class VSGitExt : IVSGitExt
         readonly IGitHubServiceProvider serviceProvider;
         readonly IVSUIContext context;
         readonly ILocalRepositoryModelFactory repositoryFactory;
+        readonly object refreshLock = new object();
 
         IGitExt gitService;
         IReadOnlyList<ILocalRepositoryModel> activeRepositories;
@@ -98,12 +99,15 @@ void RefreshActiveRepositories()
         {
             try
             {
-                log.Debug(
-                    "IGitExt.ActiveRepositories (#{Id}) returned {Repositories}",
-                    gitService.GetHashCode(),
-                    gitService?.ActiveRepositories.Select(x => x.RepositoryPath));
+                lock (refreshLock)
+                {
+                    log.Debug(
+                        "IGitExt.ActiveRepositories (#{Id}) returned {Repositories}",
+                        gitService.GetHashCode(),
+                        gitService?.ActiveRepositories.Select(x => x.RepositoryPath));
 
-                ActiveRepositories = gitService?.ActiveRepositories.Select(x => repositoryFactory.Create(x.RepositoryPath)).ToList();
+                    ActiveRepositories = gitService?.ActiveRepositories.Select(x => repositoryFactory.Create(x.RepositoryPath)).ToList();
+                }
             }
             catch (Exception e)
             {