Move hash code from hidden string to a private symbol

test/cctest/test-weakmaps.cc

Index: test/cctest/test-weakmaps.cc
diff --git a/test/cctest/test-weakmaps.cc b/test/cctest/test-weakmaps.cc
index 64d2876887bcc779044d766e9c66594478e2edb6..125557850d6391551059d4bc296b7dff676b5be8 100644
--- a/test/cctest/test-weakmaps.cc
+++ b/test/cctest/test-weakmaps.cc
@@ -89,8 +89,10 @@ TEST(Weakness) {
     Handle<Map> map = factory->NewMap(JS_OBJECT_TYPE, JSObject::kHeaderSize);
     Handle<JSObject> object = factory->NewJSObjectFromMap(map);
     Handle<Smi> smi(Smi::FromInt(23), isolate);
-    Runtime::WeakCollectionSet(weakmap, key, object);
-    Runtime::WeakCollectionSet(weakmap, object, smi);
+    int32_t hash = Object::GetOrCreateHash(isolate, key)->value();
+    Runtime::WeakCollectionSet(weakmap, key, object, hash);
+    int32_t object_hash = Object::GetOrCreateHash(isolate, object)->value();
+    Runtime::WeakCollectionSet(weakmap, object, smi, object_hash);
   }
   CHECK_EQ(2, ObjectHashTable::cast(weakmap->table())->NumberOfElements());
 
@@ -145,7 +147,8 @@ TEST(Shrinking) {
     for (int i = 0; i < 32; i++) {
       Handle<JSObject> object = factory->NewJSObjectFromMap(map);
       Handle<Smi> smi(Smi::FromInt(i), isolate);
-      Runtime::WeakCollectionSet(weakmap, object, smi);
+      int32_t object_hash = Object::GetOrCreateHash(isolate, object)->value();
+      Runtime::WeakCollectionSet(weakmap, object, smi, object_hash);
     }
   }
 
@@ -193,7 +196,8 @@ TEST(Regress2060a) {
       Handle<JSObject> object = factory->NewJSObject(function, TENURED);
       CHECK(!heap->InNewSpace(object->address()));
       CHECK(!first_page->Contains(object->address()));
-      Runtime::WeakCollectionSet(weakmap, key, object);
+      int32_t hash = Object::GetOrCreateHash(isolate, key)->value();
+      Runtime::WeakCollectionSet(weakmap, key, object, hash);
     }
   }
 
@@ -235,7 +239,8 @@ TEST(Regress2060b) {
   Handle<JSWeakMap> weakmap = AllocateJSWeakMap(isolate);
   for (int i = 0; i < 32; i++) {
     Handle<Smi> smi(Smi::FromInt(i), isolate);
-    Runtime::WeakCollectionSet(weakmap, keys[i], smi);
+    int32_t hash = Object::GetOrCreateHash(isolate, keys[i])->value();
+    Runtime::WeakCollectionSet(weakmap, keys[i], smi, hash);
   }
 
   // Force compacting garbage collection. The subsequent collections are used