Deprecate PrefixElement.importedLibraries.

pkg/analyzer/lib/dart/element/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.
 
 /**
  * Defines the element model. The element model describes the semantic (as
  * opposed to syntactic) structure of Dart code. The syntactic structure of the
  * code is modeled by the [AST structure](../ast/ast.dart).
  *
  * The element model consists of two closely related kinds of objects: elements
@@ skipping 1603 matching lines @@
 abstract class PrefixElement implements Element {
   /**
    * An empty list of prefix elements.
    */
   static const List<PrefixElement> EMPTY_LIST = const <PrefixElement>[];
 
   @override
   LibraryElement get enclosingElement;
 
   /**
-   * Return a list containing all of the libraries that are imported using this
-   * prefix.
+   * Return the empty list.
+   *
+   * Deprecated: this getter was intended to return a list containing all of
+   * the libraries that are imported using this prefix, but it was never
+   * implemented.  Due to lack of demand, it is being removed.
    */
+  @deprecated
   List<LibraryElement> get importedLibraries;
 }
 
 /**
  * A getter or a setter. Note that explicitly defined property accessors
  * implicitly define a synthetic field. Symmetrically, synthetic accessors are
  * implicitly created for explicitly defined fields. The following rules apply:
  *
  * * Every explicit field is represented by a non-synthetic [FieldElement].
  * * Every explicit field induces a getter and possibly a setter, both of which
@@ skipping 296 matching lines @@
    */
   bool get isStatic;
 
   /**
    * Return the declared type of this variable, or `null` if the variable did
    * not have a declared type (such as if it was declared using the keyword
    * 'var').
    */
   DartType get type;
 }