Don't dispose services twice

For types that have a `CancellationTokenSource` that is triggered during `Dispose()`, we should check to see if it has already been cancelled to avoid disposing twice. Implicitly, there's a race here if there are multiple threads calling `DIspose()`, but these are all handled by the DI containers we use.

src/Razor/src/Microsoft.AspNetCore.Razor.LanguageServer/Diagnostics/RazorDiagnosticsPublisher.cs

@@ -83,6 +83,11 @@ internal partial class RazorDiagnosticsPublisher : IDocumentProcessedListener, I
 
     public void Dispose()
     {
+        if (_disposeTokenSource.IsCancellationRequested)
+        {
+            return;
+        }
+
         _disposeTokenSource.Cancel();
         _disposeTokenSource.Dispose();
     }

src/Razor/src/Microsoft.AspNetCore.Razor.LanguageServer/OpenDocumentGenerator.cs

@@ -57,6 +57,11 @@ internal partial class OpenDocumentGenerator : IRazorStartupService, IDisposable
 
     public void Dispose()
     {
+        if (_disposeTokenSource.IsCancellationRequested)
+        {
+            return;
+        }
+
         _disposeTokenSource.Cancel();
         _disposeTokenSource.Dispose();
     }

src/Razor/src/Microsoft.AspNetCore.Razor.LanguageServer/ProjectSystem/RazorProjectService.cs

@@ -63,6 +63,11 @@ internal partial class RazorProjectService : IRazorProjectService, IRazorProject
 
     public void Dispose()
     {
+        if (_disposeTokenSource.IsCancellationRequested)
+        {
+            return;
+        }
+
         _disposeTokenSource.Cancel();
         _disposeTokenSource.Dispose();
     }

src/Razor/src/Microsoft.AspNetCore.Razor.LanguageServer/RazorFileChangeDetector.cs

@@ -50,6 +50,11 @@ internal partial class RazorFileChangeDetector : IFileChangeDetector, IDisposabl
 
     public void Dispose()
     {
+        if (_disposeTokenSource.IsCancellationRequested)
+        {
+            return;
+        }
+
         _disposeTokenSource.Cancel();
         _disposeTokenSource.Dispose();
     }

src/Razor/src/Microsoft.AspNetCore.Razor.LanguageServer/WorkspaceSemanticTokensRefreshNotifier.cs

@@ -43,6 +43,11 @@ internal class WorkspaceSemanticTokensRefreshNotifier : IWorkspaceSemanticTokens
 
     public void Dispose()
     {
+        if (_disposeTokenSource.IsCancellationRequested)
+        {
+            return;
+        }
+
         _optionsChangeListener.Dispose();
 
         _disposeTokenSource.Cancel();

src/Razor/src/Microsoft.CodeAnalysis.Razor.Workspaces/ProjectSystem/AbstractRazorProjectInfoDriver.cs

@@ -45,6 +45,11 @@ internal abstract partial class AbstractRazorProjectInfoDriver : IRazorProjectIn
 
     public void Dispose()
     {
+        if (_disposeTokenSource.IsCancellationRequested)
+        {
+            return;
+        }
+
         _disposeTokenSource.Cancel();
         _disposeTokenSource.Dispose();
     }

src/Razor/src/Microsoft.CodeAnalysis.Razor.Workspaces/ProjectSystem/ProjectSnapshotManager.Dispatcher.cs

@@ -168,6 +168,11 @@ internal partial class ProjectSnapshotManager
 
             public void Dispose()
             {
+                if (_disposeTokenSource.IsCancellationRequested)
+                {
+                    return;
+                }
+
                 _taskQueue.Complete();
                 _disposeTokenSource.Cancel();
                 _disposeTokenSource.Dispose();

src/Razor/src/Microsoft.VisualStudio.LanguageServices.Razor/Documents/EditorDocumentManagerListener.cs

@@ -77,6 +77,11 @@ internal partial class EditorDocumentManagerListener : IRazorStartupService, IDi
 
     public void Dispose()
     {
+        if (_disposeTokenSource.IsCancellationRequested)
+        {
+            return;
+        }
+
         _disposeTokenSource.Cancel();
         _disposeTokenSource.Dispose();
     }

src/Razor/src/Microsoft.VisualStudio.LanguageServices.Razor/DynamicFiles/BackgroundDocumentGenerator.cs

@@ -59,6 +59,11 @@ internal partial class BackgroundDocumentGenerator : IRazorStartupService, IDisp
 
     public void Dispose()
     {
+        if (_disposeTokenSource.IsCancellationRequested)
+        {
+            return;
+        }
+
         _disposeTokenSource.Cancel();
         _disposeTokenSource.Dispose();
     }

src/Razor/src/Microsoft.VisualStudio.LanguageServices.Razor/Logging/RazorActivityLog.cs

@@ -40,6 +40,11 @@ internal sealed class RazorActivityLog : IDisposable
 
     public void Dispose()
     {
+        if (_disposeTokenSource.IsCancellationRequested)
+        {
+            return;
+        }
+
         _disposeTokenSource.Cancel();
         _disposeTokenSource.Dispose();
     }

src/Razor/src/Microsoft.VisualStudio.LanguageServices.Razor/VsSolutionUpdatesProjectSnapshotChangeTrigger.cs

@@ -66,6 +66,11 @@ internal class VsSolutionUpdatesProjectSnapshotChangeTrigger : IRazorStartupServ
 
     public void Dispose()
     {
+        if (_disposeTokenSource.IsCancellationRequested)
+        {
+            return;
+        }
+
         _disposeTokenSource.Cancel();
         _disposeTokenSource.Dispose();
 

src/Razor/src/Microsoft.VisualStudio.LanguageServices.Razor/WorkspaceProjectStateChangeDetector.cs

@@ -73,6 +73,11 @@ internal partial class WorkspaceProjectStateChangeDetector : IRazorStartupServic
 
     public void Dispose()
     {
+        if (_disposeTokenSource.IsCancellationRequested)
+        {
+            return;
+        }
+
         _projectManager.Changed -= ProjectManager_Changed;
         _workspace.WorkspaceChanged -= Workspace_WorkspaceChanged;