Fix regression test on x64.

test/cctest/test-heap.cc

Index: test/cctest/test-heap.cc
diff --git a/test/cctest/test-heap.cc b/test/cctest/test-heap.cc
index c0cb582bf447147e96e00343f8edc99abd30873a..321de371fa5498778d44fe1219e387fe38629ac7 100644
--- a/test/cctest/test-heap.cc
+++ b/test/cctest/test-heap.cc
@@ -2018,6 +2018,7 @@ TEST(Regress2211) {
     DescriptorArray* descriptors = internal_obj->map()->instance_descriptors();
     ObjectHashTable* hashtable = ObjectHashTable::cast(
         internal_obj->FastPropertyAt(descriptors->GetFieldIndex(0)));
-    CHECK_LE(hashtable->SizeFor(hashtable->length()), 52);
+    // HashTable header (5) and 4 initial entries (8).
+    CHECK_LE(hashtable->SizeFor(hashtable->length()), 13 * kPointerSize);
   }
 }