Deprecate utility method

pkg/analyzer/lib/src/generated/element.dart

 // Copyright (c) 2014, 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.
 
 // This code was auto-generated, is not intended to be edited, and is subject to
 // significant change. Please see the README file for more information.
 
 library engine.element;
 
 import 'dart:collection';
@@ skipping 7075 matching lines @@
   @override
   Source get source {
     if (_definingCompilationUnit == null) {
       return null;
     }
     return _definingCompilationUnit.source;
   }
 
   @override
   List<CompilationUnitElement> get units {
-    List<CompilationUnitElement> units =
-        new List<CompilationUnitElement>(1 + _parts.length);
-    units[0] = _definingCompilationUnit;
-    JavaSystem.arraycopy(_parts, 0, units, 1, _parts.length);
+    List<CompilationUnitElement> units = new List<CompilationUnitElement>();
+    units.add(_definingCompilationUnit);
+    units.addAll(_parts);
     return units;
   }
 
   @override
   List<LibraryElement> get visibleLibraries {
     Set<LibraryElement> visibleLibraries = new Set();
     _addVisibleLibraries(visibleLibraries, false);
     return new List.from(visibleLibraries);
   }
 
@@ skipping 3314 matching lines @@
     // void <: void (by reflexivity)
     // bottom <: void (as bottom is a subtype of all types).
     // void <: dynamic (as dynamic is a supertype of all types)
     return identical(type, this) || type.isDynamic;
   }
 
   @override
   VoidTypeImpl substitute2(
       List<DartType> argumentTypes, List<DartType> parameterTypes) => this;
 }