Microsoft.CodeAnalysis.Simplification.ISimplificationService.ReduceAsync(Microsoft.CodeAnalysis.Document, System.Collections.Immutable.ImmutableArray<Microsoft.CodeAnalysis.Text.TextSpan>, Microsoft.CodeAnalysis.Simplification.SimplifierOptions, System.Collections.Immutable.ImmutableArray<Microsoft.CodeAnalysis.Simplification.AbstractReducer>, System.Threading.CancellationToken)