VM: Explicitly load function and context before calling a closure.

runtime/vm/object.cc

Index: runtime/vm/object.cc
===================================================================
--- runtime/vm/object.cc	(revision 35546)
+++ runtime/vm/object.cc	(working copy)
@@ -113,6 +113,7 @@
 RawClass* Object::void_class_ = reinterpret_cast<RawClass*>(RAW_NULL);
 RawType* Object::dynamic_type_ = reinterpret_cast<RawType*>(RAW_NULL);
 RawType* Object::void_type_ = reinterpret_cast<RawType*>(RAW_NULL);
+RawType* Object::function_type_ = reinterpret_cast<RawType*>(RAW_NULL);
 RawClass* Object::unresolved_class_class_ =
     reinterpret_cast<RawClass*>(RAW_NULL);
 RawClass* Object::type_arguments_class_ = reinterpret_cast<RawClass*>(RAW_NULL);
@@ -690,6 +691,9 @@
   cls = void_class_;
   void_type_ = Type::NewNonParameterizedType(cls);
 
+  cls = function_class_;
+  function_type_ = Type::NewNonParameterizedType(cls);
+
   // Allocate and initialize singleton true and false boolean objects.
   cls = Class::New<Bool>();
   isolate->object_store()->set_bool_class(cls);
@@ -13848,6 +13852,10 @@
   if (cls.raw() == Object::dynamic_class() && (isolate != Dart::vm_isolate())) {
     return Object::dynamic_type();
   }
+  if (cls.raw() == Object::function_class() &&
+      (isolate != Dart::vm_isolate())) {
+    return Object::function_type();
+  }
   // Fast canonical lookup/registry for simple types.
   if ((cls.NumTypeArguments() == 0) && !cls.IsSignatureClass()) {
     type = cls.CanonicalType();