'Rename Local Variable' refactoring implementation.

pkg/analysis_services/lib/search/hierarchy.dart

Index: pkg/analysis_services/lib/search/hierarchy.dart
diff --git a/pkg/analysis_services/lib/search/hierarchy.dart b/pkg/analysis_services/lib/search/hierarchy.dart
index 4fad92b3ab75c36652ad51cb1991564008320674..725dea83d34715d8e0d7a1507841e7cf85b3f79f 100644
--- a/pkg/analysis_services/lib/search/hierarchy.dart
+++ b/pkg/analysis_services/lib/search/hierarchy.dart
@@ -199,6 +199,20 @@ Set<ClassElement> getSuperClasses(ClassElement seed) {
 }
 
 
+/**
+ * If the given [element] is a synthetic [PropertyAccessorElement] returns
+ * its variable, otherwise returns [element].
+ */
+Element getSyntheticAccessorVariable(Element element) {
+  if (element is PropertyAccessorElement) {
+    if (element.isSynthetic) {
+      return element.variable;
+    }
+  }
+  return element;
+}
+
+
 typedef void _ElementProcessor(Element element);
 
 /**