Microsoft.CodeAnalysis.Completion.Providers.IRemoteExtensionMethodImportCompletionService.GetUnimportedExtensionMethodsAsync(Microsoft.CodeAnalysis.Checksum, Microsoft.CodeAnalysis.DocumentId, System.Int32, System.String, System.Collections.Immutable.ImmutableArray<System.String>, System.Collections.Immutable.ImmutableArray<System.String>, System.Boolean, System.Boolean, System.Threading.CancellationToken)