Pass undefined to JS builtins when called with implicit receiver.

src/x64/lithium-codegen-x64.cc

Index: src/x64/lithium-codegen-x64.cc
diff --git a/src/x64/lithium-codegen-x64.cc b/src/x64/lithium-codegen-x64.cc
index 97177de6ea3577b68f48a4933c649de2b3aab0c2..fa5d63648ac82397dc39f4a98b537a179a8872f6 100644
--- a/src/x64/lithium-codegen-x64.cc
+++ b/src/x64/lithium-codegen-x64.cc
@@ -144,7 +144,7 @@ bool LCodeGen::GeneratePrologue() {
   // when called as functions (without an explicit receiver
   // object). rcx is zero for method calls and non-zero for function
   // calls.
-  if (info_->is_strict_mode()) {
+  if (info_->is_strict_mode() || info_->is_es5_native()) {
     Label ok;
     __ testq(rcx, rcx);
     __ j(zero, &ok, Label::kNear);