Keep track of script objects in a weak fixed array.

src/objects-inl.h

Index: src/objects-inl.h
diff --git a/src/objects-inl.h b/src/objects-inl.h
index b3713b644c5dfe9b39339d05a953e4858f6e3aa9..933360c59fa41a462ed9e3997e2346a0f59db395 100644
--- a/src/objects-inl.h
+++ b/src/objects-inl.h
@@ -877,9 +877,6 @@ bool Object::IsWeakHashTable() const {
 }
 
 
-bool Object::IsWeakValueHashTable() const { return IsHashTable(); }
-
-
 bool Object::IsDictionary() const {
   return IsHashTable() &&
       this != HeapObject::cast(this)->GetHeap()->string_table();
@@ -3319,7 +3316,6 @@ CAST_ACCESSOR(UnseededNumberDictionary)
 CAST_ACCESSOR(WeakCell)
 CAST_ACCESSOR(WeakFixedArray)
 CAST_ACCESSOR(WeakHashTable)
-CAST_ACCESSOR(WeakValueHashTable)
 
 
 // static