Use OrderedHashTables as the backing store of JSSet and JSMap

src/objects-debug.cc

Index: src/objects-debug.cc
diff --git a/src/objects-debug.cc b/src/objects-debug.cc
index ba9ff65be0c4883b97685076fdeef82e9f528671..cfcfd1c90a19ea17483098f74fa672338ed77023 100644
--- a/src/objects-debug.cc
+++ b/src/objects-debug.cc
@@ -677,7 +677,7 @@ void JSSet::JSSetVerify() {
   CHECK(IsJSSet());
   JSObjectVerify();
   VerifyHeapPointer(table());
-  CHECK(table()->IsHashTable() || table()->IsUndefined());
+  CHECK(table()->IsOrderedHashSet() || table()->IsUndefined());
 }
 
 
@@ -685,7 +685,7 @@ void JSMap::JSMapVerify() {
   CHECK(IsJSMap());
   JSObjectVerify();
   VerifyHeapPointer(table());
-  CHECK(table()->IsHashTable() || table()->IsUndefined());
+  CHECK(table()->IsOrderedHashMap() || table()->IsUndefined());
 }