Fast path for strict closure creation.

src/x64/codegen-x64.cc

Index: src/x64/codegen-x64.cc
diff --git a/src/x64/codegen-x64.cc b/src/x64/codegen-x64.cc
index 8074b4a38a3d7fc21b17430a6bab333e67798cdd..792efd77b0a96e32b5cdfcbc8077b3cb7aa22ad5 100644
--- a/src/x64/codegen-x64.cc
+++ b/src/x64/codegen-x64.cc
@@ -4263,9 +4263,9 @@ void CodeGenerator::InstantiateFunction(
   // space for nested functions that don't need literals cloning.
   if (!pretenure &&
       scope()->is_function_scope() &&
-      function_info->num_literals() == 0 &&
-      !function_info->strict_mode()) {  // Strict mode functions use slow path.
-    FastNewClosureStub stub;
+      function_info->num_literals() == 0) {
+    FastNewClosureStub stub(
+        function_info->strict_mode() ? kStrictMode : kNonStrictMode);
     frame_->Push(function_info);
     Result answer = frame_->CallStub(&stub, 1);
     frame_->Push(&answer);