Add begin events for const and new expressions.

pkg/compiler/lib/src/parser/node_listener.dart

Index: pkg/compiler/lib/src/parser/node_listener.dart
diff --git a/pkg/compiler/lib/src/parser/node_listener.dart b/pkg/compiler/lib/src/parser/node_listener.dart
index f70ccbc4dd8cc5fc7492521bb3bfb261e6ffd49b..3ad07203e166bad14e73f25ed0ca0737dacc941c 100644
--- a/pkg/compiler/lib/src/parser/node_listener.dart
+++ b/pkg/compiler/lib/src/parser/node_listener.dart
@@ -722,16 +722,16 @@ class NodeListener extends ElementListener {
   }
 
   @override
-  void handleNewExpression(Token token) {
+  void endNewExpression(Token token) {
     NodeList arguments = popNode();
     Node name = popNode();
     pushNode(new NewExpression(token, new Send(null, name, arguments)));
   }
 
   @override
-  void handleConstExpression(Token token) {
+  void endConstExpression(Token token) {
     // [token] carries the 'const' information.
-    handleNewExpression(token);
+    endNewExpression(token);
   }
 
   @override