Update deprecated maps before generating optimized code.

src/ast.h

Index: src/ast.h
diff --git a/src/ast.h b/src/ast.h
index 10ae7de458d1653e36a7ab688dd15b9b68e297f4..b36d9677081d4ec17e7203e4909cdb22bd0d4c80 100644
--- a/src/ast.h
+++ b/src/ast.h
@@ -277,6 +277,14 @@ class SmallMapList {
   bool is_empty() const { return list_.is_empty(); }
   int length() const { return list_.length(); }
 
+  void AddMapIfMissing(Handle<Map> map, Zone* zone) {
+    map = Map::CurrentMapForDeprecated(map);
+    for (int i = 0; i < length(); ++i) {
+      if (at(i).is_identical_to(map)) return;
+    }
+    Add(map, zone);
+  }
+
   void Add(Handle<Map> handle, Zone* zone) {
     list_.Add(handle.location(), zone);
   }