Deprecate PrefixElement.importedLibraries.

pkg/analyzer/lib/src/generated/element_handle.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.
 
 library analyzer.src.generated.element_handle;
 
 import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/dart/element/type.dart';
 import 'package:analyzer/src/dart/element/element.dart';
 import 'package:analyzer/dart/ast/ast.dart';
@@ skipping 897 matching lines @@
       : super(resynthesizer, location);
 
   @override
   PrefixElement get actualElement => super.actualElement as PrefixElement;
 
   @override
   LibraryElement get enclosingElement =>
       super.enclosingElement as LibraryElement;
 
   @override
-  List<LibraryElement> get importedLibraries => actualElement.importedLibraries;
+  List<LibraryElement> get importedLibraries => LibraryElement.EMPTY_LIST;
 
   @override
   ElementKind get kind => ElementKind.PREFIX;
 }
 
 /**
  * Instances of the class `PropertyAccessorElementHandle` implement a handle to a
  * `PropertyAccessorElement`.
  */
 class PropertyAccessorElementHandle extends ExecutableElementHandle
@@ skipping 164 matching lines @@
 }
 
 /**
  * TODO(scheglov) invalid implementation
  */
 class WeakReference<T> {
   final T value;
   WeakReference(this.value);
   T get() => value;
 }