Simplify processing of errors reported by the build

src/Features/Core/Portable/Diagnostics/IDiagnosticAnalyzerService.cs

@@ -87,12 +87,6 @@ Task<ImmutableArray<DiagnosticData>> GetDiagnosticsForSpanAsync(
     Task<ImmutableArray<DiagnosticDescriptor>> GetDiagnosticDescriptorsAsync(
         Solution solution, ProjectId projectId, AnalyzerReference analyzerReference, string language, CancellationToken cancellationToken);
 
-    /// <summary>
-    /// Given a list of errors ids (like CS1234), attempts to find an associated descriptor for each id.
-    /// </summary>
-    Task<ImmutableDictionary<string, DiagnosticDescriptor>> TryGetDiagnosticDescriptorsAsync(
-        Solution solution, ImmutableArray<string> diagnosticIds, CancellationToken cancellationToken);
-
     /// <inheritdoc cref="HostDiagnosticAnalyzers.GetDiagnosticDescriptorsPerReference(DiagnosticAnalyzerInfoCache)"/>
     Task<ImmutableDictionary<string, ImmutableArray<DiagnosticDescriptor>>> GetDiagnosticDescriptorsPerReferenceAsync(
         Solution solution, CancellationToken cancellationToken);

src/Features/Core/Portable/Diagnostics/Service/DiagnosticAnalyzerService_RemoteOrLocalDispatcher.cs

@@ -60,35 +60,6 @@ public async Task<ImmutableArray<DiagnosticDescriptor>> GetDiagnosticDescriptors
             .SelectManyAsArray(this._analyzerInfoCache.GetDiagnosticDescriptors);
     }
 
-    public async Task<ImmutableDictionary<string, DiagnosticDescriptor>> TryGetDiagnosticDescriptorsAsync(
-        Solution solution, ImmutableArray<string> diagnosticIds, CancellationToken cancellationToken)
-    {
-        var client = await RemoteHostClient.TryGetClientAsync(solution.Services, cancellationToken).ConfigureAwait(false);
-        if (client is not null)
-        {
-            var map = await client.TryInvokeAsync<IRemoteDiagnosticAnalyzerService, ImmutableDictionary<string, DiagnosticDescriptorData>>(
-                solution,
-                (service, solution, cancellationToken) => service.TryGetDiagnosticDescriptorsAsync(solution, diagnosticIds, cancellationToken),
-                cancellationToken).ConfigureAwait(false);
-
-            if (!map.HasValue)
-                return ImmutableDictionary<string, DiagnosticDescriptor>.Empty;
-
-            return map.Value.ToImmutableDictionary(
-                kvp => kvp.Key,
-                kvp => kvp.Value.ToDiagnosticDescriptor());
-        }
-
-        var builder = ImmutableDictionary.CreateBuilder<string, DiagnosticDescriptor>();
-        foreach (var diagnosticId in diagnosticIds)
-        {
-            if (this._analyzerInfoCache.TryGetDescriptorForDiagnosticId(diagnosticId, out var descriptor))
-                builder[diagnosticId] = descriptor;
-        }
-
-        return builder.ToImmutable();
-    }
-
     public async Task<ImmutableDictionary<string, ImmutableArray<DiagnosticDescriptor>>> GetDiagnosticDescriptorsPerReferenceAsync(Solution solution, CancellationToken cancellationToken)
     {
         var client = await RemoteHostClient.TryGetClientAsync(solution.Services, cancellationToken).ConfigureAwait(false);

src/VisualStudio/Core/Def/TaskList/ExternalErrorDiagnosticUpdateSource.cs

@@ -40,8 +40,6 @@ namespace Microsoft.VisualStudio.LanguageServices.Implementation.TaskList;
 internal sealed class ExternalErrorDiagnosticUpdateSource : IDisposable
 {
     private readonly Workspace _workspace;
-    public readonly IAsynchronousOperationListener Listener;
-    public readonly CancellationToken DisposalToken;
     private readonly IServiceBroker _serviceBroker;
 
     /// <summary>
@@ -70,17 +68,14 @@ public ExternalErrorDiagnosticUpdateSource(
         [Import(typeof(SVsFullAccessServiceBroker))] IServiceBroker serviceBroker,
         IThreadingContext threadingContext)
     {
-        DisposalToken = threadingContext.DisposalToken;
         _workspace = workspace;
-        Listener = listenerProvider.GetListener(FeatureAttribute.ErrorList);
 
         _serviceBroker = serviceBroker;
         _taskQueue = new AsyncBatchingWorkQueue<Func<CancellationToken, Task>>(
             TimeSpan.Zero,
             processBatchAsync: ProcessTaskQueueItemsAsync,
-            Listener,
-            DisposalToken
-        );
+            listenerProvider.GetListener(FeatureAttribute.ErrorList),
+            threadingContext.DisposalToken);
 
         // This pattern ensures that we are called whenever the build starts/completes even if it is already in progress.
         KnownUIContexts.SolutionBuildingContext.WhenActivated(() =>