Use NeedsContext() instead of comparing num_heap_slots().

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 f859eabc381ed2a65284a08b921227630d5271ec..bba9921e1c200342d82ea207c1350f7ffc24cc24 100644
--- a/src/full-codegen/arm64/full-codegen-arm64.cc
+++ b/src/full-codegen/arm64/full-codegen-arm64.cc
@@ -170,7 +170,7 @@ void FullCodeGenerator::Generate() {
 
   bool function_in_register_x1 = true;
 
-  if (info->scope()->num_heap_slots() > 0) {
+  if (info->scope()->NeedsContext()) {
     // Argument to NewContext is the function, which is still in x1.
     Comment cmnt(masm_, "[ Allocate context");
     bool need_write_barrier = true;
@@ -1200,7 +1200,7 @@ MemOperand FullCodeGenerator::ContextSlotOperandCheckExtensions(Variable* var,
   Register temp = x11;
 
   for (Scope* s = scope(); s != var->scope(); s = s->outer_scope()) {
-    if (s->num_heap_slots() > 0) {
+    if (s->NeedsContext()) {
       if (s->calls_sloppy_eval()) {
         // Check that extension is "the hole".
         __ Ldr(temp, ContextMemOperand(context, Context::EXTENSION_INDEX));