Track representations of fields

src/heap.cc

Index: src/heap.cc
diff --git a/src/heap.cc b/src/heap.cc
index 10cb4738abdf66c07be84b3900eeb9dd2d95c553..9ec4e7d01eb0ab4991ab1c9d92cc3d8884890717 100644
--- a/src/heap.cc
+++ b/src/heap.cc
@@ -4146,7 +4146,9 @@ MaybeObject* Heap::AllocateInitialMap(JSFunction* fun) {
       for (int i = 0; i < count; i++) {
         String* name = fun->shared()->GetThisPropertyAssignmentName(i);
         ASSERT(name->IsInternalizedString());
-        FieldDescriptor field(name, i, NONE, i + 1);
+        // TODO(verwaest): Since we cannot update the boilerplate's map yet,
+        // initialize to the worst case.
+        FieldDescriptor field(name, i, NONE, Representation::Tagged(), i + 1);
         descriptors->Set(i, &field, witness);
       }
       descriptors->Sort();
@@ -4580,6 +4582,7 @@ MaybeObject* Heap::AllocateGlobalObject(JSFunction* constructor) {
     ASSERT(details.type() == CALLBACKS);  // Only accessors are expected.
     PropertyDetails d = PropertyDetails(details.attributes(),
                                         CALLBACKS,
+                                        Representation::None(),
                                         details.descriptor_index());
     Object* value = descs->GetCallbacksObject(i);
     MaybeObject* maybe_value = AllocateJSGlobalPropertyCell(value);