Keep types in signatures of function types properly instantiated as the function

runtime/vm/bootstrap_natives.h

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #ifndef RUNTIME_VM_BOOTSTRAP_NATIVES_H_
 #define RUNTIME_VM_BOOTSTRAP_NATIVES_H_
 
 #include "vm/native_entry.h"
 
 // bootstrap dart natives used in the core dart library.
@@ skipping 384 matching lines @@
   V(LibraryMirror_fromPrefix, 1)                                               \
   V(LibraryMirror_invoke, 5)                                                   \
   V(LibraryMirror_invokeGetter, 3)                                             \
   V(LibraryMirror_invokeSetter, 4)                                             \
   V(TypeVariableMirror_owner, 1)                                               \
   V(TypeVariableMirror_upper_bound, 1)                                         \
   V(DeclarationMirror_location, 1)                                             \
   V(DeclarationMirror_metadata, 1)                                             \
   V(FunctionTypeMirror_call_method, 2)                                         \
   V(FunctionTypeMirror_parameters, 2)                                          \
-  V(FunctionTypeMirror_return_type, 2)                                         \
+  V(FunctionTypeMirror_return_type, 1)                                         \
   V(MethodMirror_owner, 2)                                                     \
   V(MethodMirror_parameters, 2)                                                \
   V(MethodMirror_return_type, 2)                                               \
   V(MethodMirror_source, 1)                                                    \
   V(ParameterMirror_type, 3)                                                   \
   V(TypedefMirror_referent, 1)                                                 \
   V(TypedefMirror_declaration, 1)                                              \
   V(VariableMirror_type, 2)
 
 class BootstrapNatives : public AllStatic {
@@ skipping 11 matching lines @@
 #if !defined(PRODUCT) && !defined(DART_PRECOMPILED_RUNTIME)
   MIRRORS_BOOTSTRAP_NATIVE_LIST(DECLARE_BOOTSTRAP_NATIVE)
 #endif
 
 #undef DECLARE_BOOTSTRAP_NATIVE
 };
 
 }  // namespace dart
 
 #endif  // RUNTIME_VM_BOOTSTRAP_NATIVES_H_