Remove parent_level field of function type parameters.

runtime/vm/kernel_reader.cc

Index: runtime/vm/kernel_reader.cc
diff --git a/runtime/vm/kernel_reader.cc b/runtime/vm/kernel_reader.cc
index 231300e595be74842e241850bdf2144a308c403b..6fe2d47084b2c1b7f8a9a914590f3cd2a20482f0 100644
--- a/runtime/vm/kernel_reader.cc
+++ b/runtime/vm/kernel_reader.cc
@@ -243,7 +243,7 @@ void KernelReader::ReadPreliminaryClass(dart::Class* klass,
     type_parameters = TypeArguments::New(num_type_parameters);
     for (intptr_t i = 0; i < num_type_parameters; i++) {
       parameter = dart::TypeParameter::New(
-          *klass, Function::Handle(Z), i, 0,
+          *klass, Function::Handle(Z), i,
           H.DartSymbol(kernel_klass->type_parameters()[i]->name()), null_bound,
           TokenPosition::kNoSource);
       type_parameters.SetTypeAt(i, parameter);