Track computed literal properties.

src/objects-inl.h

Index: src/objects-inl.h
diff --git a/src/objects-inl.h b/src/objects-inl.h
index be4af06116e5aadefc8b4b467672a9b5d1446433..86faf6e1452a8b4c01510f4066ae06d55d297cc5 100644
--- a/src/objects-inl.h
+++ b/src/objects-inl.h
@@ -292,6 +292,9 @@ MaybeObject* Object::AllocateNewStorageFor(Heap* heap,
                                            PretenureFlag tenure) {
   if (!FLAG_track_double_fields) return this;
   if (!representation.IsDouble()) return this;
+  if (IsUndefined()) {
+    return heap->AllocateHeapNumber(0, tenure);
+  }
   return heap->AllocateHeapNumber(Number(), tenure);
 }
 
@@ -1541,7 +1544,7 @@ MaybeObject* JSObject::MigrateInstance() {
   // Converting any field to the most specific type will cause the
   // GeneralizeFieldRepresentation algorithm to create the most general existing
   // transition that matches the object. This achieves what is needed.
-  return GeneralizeFieldRepresentation(0, Representation::Smi());
+  return GeneralizeFieldRepresentation(0, Representation::None());
 }
 
 
@@ -2366,7 +2369,6 @@ void DescriptorArray::Set(int descriptor_number,
   // Range check.
   ASSERT(descriptor_number < number_of_descriptors());
 
-  ASSERT(!desc->GetDetails().representation().IsNone());
   NoIncrementalWriteBarrierSet(this,
                                ToKeyIndex(descriptor_number),
                                desc->GetKey());
@@ -2382,7 +2384,6 @@ void DescriptorArray::Set(int descriptor_number,
 void DescriptorArray::Set(int descriptor_number, Descriptor* desc) {
   // Range check.
   ASSERT(descriptor_number < number_of_descriptors());
-  ASSERT(!desc->GetDetails().representation().IsNone());
 
   set(ToKeyIndex(descriptor_number), desc->GetKey());
   set(ToValueIndex(descriptor_number), desc->GetValue());
@@ -3617,6 +3618,9 @@ bool Map::CanBeDeprecated() {
   int descriptor = LastAdded();
   for (int i = 0; i <= descriptor; i++) {
     PropertyDetails details = instance_descriptors()->GetDetails(i);
+    if (FLAG_track_fields && details.representation().IsNone()) {
+      return true;
+    }
     if (FLAG_track_fields && details.representation().IsSmi()) {
       return true;
     }