Add an assert to check that things ended up how we expected

I'm doing an assert here rather than throwing because although this
is an expectation, I don't imagine anything will be terribly wrong
for the user if it's violated. But throwing would definitely make things
bad.

Author: jasonmalinowski

src/LanguageServer/Microsoft.CodeAnalysis.LanguageServer/HostWorkspace/LanguageServerProjectLoader.cs

@@ -281,6 +281,10 @@ private async Task<bool> ReloadProjectAsync(ProjectToLoad projectToLoad, ToastEr
                     await primordialProjectFactory.ApplyChangeToWorkspaceAsync(workspace => workspace.OnProjectRemoved(projectId), cancellationToken);
                 }
 
+                // At this point we expect that all the loaded projects are now in the project factory returned, and any previous ones have been removed.
+                // this is a Debug.Assert() because if this expectation fails, the user's probably still in a state where things will work just fine;
+                // throwing here would mean we don't remember the LoadedProjects we created, and the next update will create more and things will get really broken.
+                Debug.Assert(newProjectTargets.All(target => target.ProjectFactory == projectFactory));
                 _loadedProjects[projectPath] = new ProjectLoadState.LoadedTargets(newProjectTargets);
             }