Remove unused field

src/Workspaces/Core/Portable/FindSymbols/SymbolFinder.FindLiteralsServerCallback.cs

@@ -14,16 +14,13 @@ internal sealed class FindLiteralsServerCallback
         {
             private readonly Solution _solution;
             private readonly IStreamingFindLiteralReferencesProgress _progress;
-            private readonly CancellationToken _cancellationToken;
 
             public FindLiteralsServerCallback(
                 Solution solution,
-                IStreamingFindLiteralReferencesProgress progress,
-                CancellationToken cancellationToken)
+                IStreamingFindLiteralReferencesProgress progress)
             {
                 _solution = solution;
                 _progress = progress;
-                _cancellationToken = cancellationToken;
             }
 
             public Task AddItemsAsync(int count)

src/Workspaces/Core/Portable/FindSymbols/SymbolFinder_FindLiteralReferences.cs

@@ -27,7 +27,7 @@ public static partial class SymbolFinder
                     // Create a callback that we can pass to the server process to hear about the 
                     // results as it finds them.  When we hear about results we'll forward them to
                     // the 'progress' parameter which will then update the UI.
-                    var serverCallback = new FindLiteralsServerCallback(solution, progress, cancellationToken);
+                    var serverCallback = new FindLiteralsServerCallback(solution, progress);
 
                     var success = await client.TryRunRemoteAsync(
                         WellKnownServiceHubServices.CodeAnalysisService,