The forward declaration of Dart_SetReturnValue in native_arguments.h

vm/native_arguments.h

Index: vm/native_arguments.h
===================================================================
--- vm/native_arguments.h	(revision 11717)
+++ vm/native_arguments.h	(working copy)
@@ -39,9 +39,7 @@
 
 #endif
 
-DART_EXTERN_C {
-  void Dart_SetReturnValue(Dart_NativeArguments, Dart_Handle);
-}
+void SetReturnValueHelper(Dart_NativeArguments, Dart_Handle);
 
 // Class NativeArguments is used to access arguments passed in from
 // generated dart code to a runtime function or a dart library native
@@ -81,7 +79,7 @@
 
  private:
   friend class BootstrapNatives;
-  friend void Dart_SetReturnValue(Dart_NativeArguments, Dart_Handle);
+  friend void SetReturnValueHelper(Dart_NativeArguments, Dart_Handle);
 
   // Since this function is passed a RawObject directly, we need to be
   // exceedingly careful when we use it.  If there are any other side