Clear navigator when repository changes.

Previously we were only clearing it when it changes to a new valid repository. Instead clear it if the TE context is cleared for example. We need to check that the repository is actually different here because `TeamExplorerRepositoryHolder` sometimes notifies a change when the repository has not changed.

Author: grokys

src/GitHub.App/ViewModels/GitHubPane/GitHubPaneViewModel.cs

@@ -46,6 +46,7 @@ public sealed class GitHubPaneViewModel : ViewModelBase, IGitHubPaneViewModel, I
         readonly ReactiveCommand<Unit> refresh;
         readonly ReactiveCommand<Unit> showPullRequests;
         readonly ReactiveCommand<object> openInBrowser;
+        bool initialized;
         IViewModel content;
         ILocalRepositoryModel localRepository;
         string searchQuery;
@@ -343,10 +344,13 @@ async Task NavigateTo<TViewModel>(Func<TViewModel, Task> initialize, Func<TViewM
 
         async Task UpdateContent(ILocalRepositoryModel repository)
         {
+            if (initialized && Equals(repository, LocalRepository)) return;
+
+            initialized = true;
             LocalRepository = repository;
             Connection = null;
-
             Content = null;
+            navigator.Clear();
 
             if (repository == null)
             {
@@ -372,7 +376,6 @@ async Task UpdateContent(ILocalRepositoryModel repository)
 
                 if (Connection != null)
                 {
-                    navigator.Clear();
                     Content = navigator;
                     await ShowDefaultPage();
                 }