Remove BuildFunctionTypeAliasesTask.

pkg/analyzer/lib/src/task/dart_work_manager.dart

 // Copyright (c) 2015, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library analyzer.src.task.dart_work_manager;
 
 import 'dart:collection';
 
 import 'package:analyzer/src/context/cache.dart';
 import 'package:analyzer/src/generated/engine.dart'
@@ skipping 24 matching lines @@
     BUILD_DIRECTIVES_ERRORS,
     BUILD_LIBRARY_ERRORS,
     PARSE_ERRORS,
     SCAN_ERRORS
   ];
 
   /**
    * The list of errors that are reported for raw Dart [LibrarySpecificUnit]s.
    */
   static final List<ResultDescriptor> _UNIT_ERRORS = <ResultDescriptor>[
-    BUILD_FUNCTION_TYPE_ALIASES_ERRORS,
     HINTS,
     RESOLVE_REFERENCES_ERRORS,
     RESOLVE_TYPE_NAMES_ERRORS,
     VARIABLE_REFERENCE_ERRORS,
     VERIFY_ERRORS
   ];
 
   final InternalAnalysisContext context;
 
   /**
@@ skipping 382 matching lines @@
     }
   }
 
   bool _shouldErrorsBeComputed(Source source) =>
       context.shouldErrorsBeAnalyzed(source, null);
 
   static bool _isDartSource(AnalysisTarget target) {
     return target is Source && AnalysisEngine.isDartFileName(target.fullName);
   }
 }