Add sharedfrontend package

pkg/analyzer2dart/lib/src/tree_shaker.dart

Index: pkg/analyzer2dart/lib/src/tree_shaker.dart
diff --git a/pkg/analyzer2dart/lib/src/tree_shaker.dart b/pkg/analyzer2dart/lib/src/tree_shaker.dart
index 7e765ccf8cdfd7a3a73cd712b6f2f8f4f9cc637a..5427866d569fec07d6517843a0c2db3d39330e78 100644
--- a/pkg/analyzer2dart/lib/src/tree_shaker.dart
+++ b/pkg/analyzer2dart/lib/src/tree_shaker.dart
@@ -11,6 +11,7 @@ import 'package:analyzer/src/generated/element.dart';
 import 'package:analyzer/src/generated/source.dart';
 import 'package:analyzer/src/generated/resolver.dart';
 import 'package:compiler/src/universe/universe.dart';
+import 'package:sharedfrontend/src/access_semantics.dart';
 
 import 'closed_world.dart';
 import 'util.dart';
@@ -310,13 +311,13 @@ class TreeShakingVisitor extends SemanticVisitor {
   void handleDynamicAccess(AccessSemantics semantics) {
     if (semantics.isRead) {
       analysis.invokes.add(
-          new Selector.getter(semantics.identifier.name, null));
+          new Selector.getter(semantics.name, null));
     }
     if (semantics.isWrite) {
       // Selector.setter constructor uses the convention that setter names
       // don't end in '='.
       analysis.invokes.add(
-          new Selector.setter(semantics.identifier.name, null));
+          new Selector.setter(semantics.name, null));
     }
   }