[es6] Fix invalid ToString in implementation of ToName.

src/full-codegen/arm64/full-codegen-arm64.cc

Index: src/full-codegen/arm64/full-codegen-arm64.cc
diff --git a/src/full-codegen/arm64/full-codegen-arm64.cc b/src/full-codegen/arm64/full-codegen-arm64.cc
index d3a159712f1e88151bcad5e1f4e19db6b8554cad..19096b5b391906803ce9745ce3d9c7c0fa51113f 100644
--- a/src/full-codegen/arm64/full-codegen-arm64.cc
+++ b/src/full-codegen/arm64/full-codegen-arm64.cc
@@ -3514,8 +3514,8 @@ void FullCodeGenerator::EmitToName(CallRuntime* expr) {
   STATIC_ASSERT(FIRST_NAME_TYPE == FIRST_TYPE);
   __ JumpIfObjectType(x0, x1, x1, LAST_NAME_TYPE, &done_convert, ls);
   __ Bind(&convert);
-  ToStringStub stub(isolate());
-  __ CallStub(&stub);
+  __ Push(x0);
+  __ CallRuntime(Runtime::kToName, 1);
   __ Bind(&done_convert);
   context()->Plug(x0);
 }