Optimize add/set/delete operations for string keys in Maps and Sets

src/hydrogen-instructions.h

Index: src/hydrogen-instructions.h
diff --git a/src/hydrogen-instructions.h b/src/hydrogen-instructions.h
index 8518fdca09de7944a0784099164fc6ced420ea3a..b5d2f5176cf381b67f61883a21dbfd196610bcf7 100644
--- a/src/hydrogen-instructions.h
+++ b/src/hydrogen-instructions.h
@@ -6360,6 +6360,13 @@ class HObjectAccess FINAL {
                          Representation::Smi());
   }
 
+  template <typename CollectionType>
+  static HObjectAccess ForOrderedHashTableNumberOfDeletedElements() {
+    return HObjectAccess(kInobject,
+                         CollectionType::kNumberOfDeletedElementsOffset,
+                         Representation::Smi());
+  }
+
   inline bool Equals(HObjectAccess that) const {
     return value_ == that.value_;  // portion and offset must match
   }