Set empty LocalVarDescriptors on execute-once functions

runtime/vm/compiler.cc

Index: runtime/vm/compiler.cc
diff --git a/runtime/vm/compiler.cc b/runtime/vm/compiler.cc
index 87ca181198a8e4569450492c795f6c5a8a804080..1ec0d3fa5e43bed04df77ef4b3920c2435fb0a1f 100644
--- a/runtime/vm/compiler.cc
+++ b/runtime/vm/compiler.cc
@@ -1339,6 +1339,8 @@ RawObject* Compiler::EvaluateStaticInitializer(const Field& field) {
                                   false,  // optimized
                                   Isolate::kNoDeoptId);
       initializer = parsed_function->function().raw();
+      Code::Handle(initializer.unoptimized_code()).set_var_descriptors(
+          Object::empty_var_descriptors());
     } else {
       initializer ^= field.PrecompiledInitializer();
     }
@@ -1406,6 +1408,8 @@ RawObject* Compiler::ExecuteOnce(SequenceNode* fragment) {
                                 parsed_function,
                                 false,
                                 Isolate::kNoDeoptId);
+    Code::Handle(func.unoptimized_code()).set_var_descriptors(
+        Object::empty_var_descriptors());
 
     const Object& result = PassiveObject::Handle(
         DartEntry::InvokeFunction(func, Object::empty_array()));