Eliminate map checks of constant values.

src/objects-inl.h

Index: src/objects-inl.h
diff --git a/src/objects-inl.h b/src/objects-inl.h
index c12a12a6bcd9bef8c673712d235bbb4ecb48d3fd..88ac91ce47deebf244879ec5963926c538408fd4 100644
--- a/src/objects-inl.h
+++ b/src/objects-inl.h
@@ -3669,6 +3669,12 @@ bool Map::CanOmitPrototypeChecks() {
 }
 
 
+bool Map::CanOmitMapChecks() {
+  return !HasTransitionArray() && !is_dictionary_map() &&
+         FLAG_omit_map_checks_for_leaf_maps;
+}
+
+
 int DependentCode::number_of_entries(DependencyGroup group) {
   if (length() == 0) return 0;
   return Smi::cast(get(group))->value();