Fix bad optimization prematurely marking types as instantiated (issue 8710).

runtime/vm/object.cc

Index: runtime/vm/object.cc
===================================================================
--- runtime/vm/object.cc	(revision 19100)
+++ runtime/vm/object.cc	(working copy)
@@ -747,7 +747,7 @@
   type ^= Type::New(Object::Handle(cls.raw()),
                     TypeArguments::Handle(),
                     Scanner::kDummyTokenIndex);
-  type.set_is_finalized_instantiated();
+  type.SetIsFinalized();
   type ^= type.Canonicalize();
   object_store->set_array_type(type);
 
@@ -8728,7 +8728,7 @@
   }
   const Type& type = Type::Handle(
       Type::New(cls, type_arguments, Scanner::kDummyTokenIndex));
-  type.set_is_finalized_instantiated();
+  type.SetIsFinalized();
   return type.raw();
 }
 
@@ -9291,24 +9291,22 @@
   type ^= Type::New(Object::Handle(type_class.raw()),
                     no_type_arguments,
                     Scanner::kDummyTokenIndex);
-  type.set_is_finalized_instantiated();
+  type.SetIsFinalized();
   type ^= type.Canonicalize();
   return type.raw();
 }
 
 
-void Type::set_is_finalized_instantiated() const {
+void Type::SetIsFinalized() const {
   ASSERT(!IsFinalized());
-  set_type_state(RawType::kFinalizedInstantiated);
+  if (IsInstantiated()) {
+    set_type_state(RawType::kFinalizedInstantiated);
+  } else {
+    set_type_state(RawType::kFinalizedUninstantiated);
+  }
 }
 
 
-void Type::set_is_finalized_uninstantiated() const {
-  ASSERT(!IsFinalized());
-  set_type_state(RawType::kFinalizedUninstantiated);
-}
-
-
 void Type::set_is_being_finalized() const {
   ASSERT(!IsFinalized() && !IsBeingFinalized());
   set_type_state(RawType::kBeingFinalized);
@@ -9419,7 +9417,7 @@
       Type::New(cls, type_arguments, token_pos()));
   ASSERT(type_arguments.IsNull() ||
          (type_arguments.Length() == cls.NumTypeArguments()));
-  instantiated_type.set_is_finalized_instantiated();
+  instantiated_type.SetIsFinalized();
   return instantiated_type.raw();
 }