Remove Element.users support.

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

Index: pkg/analyzer/lib/src/generated/element_handle.dart
diff --git a/pkg/analyzer/lib/src/generated/element_handle.dart b/pkg/analyzer/lib/src/generated/element_handle.dart
index b84e36e00803bfdcdbc37daa996dc7a85105a064..d732ff404df842fc5146734b4351326bd1f28356 100644
--- a/pkg/analyzer/lib/src/generated/element_handle.dart
+++ b/pkg/analyzer/lib/src/generated/element_handle.dart
@@ -7,8 +7,6 @@
 
 library engine.element_handle;
 
-import 'package:analyzer/src/generated/utilities_collection.dart';
-
 import 'ast.dart';
 import 'element.dart';
 import 'engine.dart';
@@ -374,12 +372,6 @@ abstract class ElementHandle implements Element {
   @override
   CompilationUnit get unit => actualElement.unit;
 
-  /**
-   * Identifiers of the elements that use this elements.
-   */
-  @override
-  IntSet get users => new IntSet();
-
   @override
   bool operator ==(Object object) =>
       object is Element && object.location == _location;
@@ -387,13 +379,6 @@ abstract class ElementHandle implements Element {
   @override
   accept(ElementVisitor visitor) => actualElement.accept(visitor);
 
-  /**
-   * Remember the given [element] as a user of this element.
-   */
-  @override
-  void addUser(Element element) {
-  }
-
   @override
   String computeDocumentationComment() =>
       actualElement.computeDocumentationComment();