Use NeedsContext() instead of comparing num_heap_slots().

src/full-codegen/mips/full-codegen-mips.cc

Index: src/full-codegen/mips/full-codegen-mips.cc
diff --git a/src/full-codegen/mips/full-codegen-mips.cc b/src/full-codegen/mips/full-codegen-mips.cc
index 6601dee3773fda6986406dfe8c0dcb8adc6887ea..7c398ab0dd0e250b8125a9a40aad7034ccc5aca4 100644
--- a/src/full-codegen/mips/full-codegen-mips.cc
+++ b/src/full-codegen/mips/full-codegen-mips.cc
@@ -177,7 +177,7 @@ void FullCodeGenerator::Generate() {
   bool function_in_register_a1 = true;
 
   // Possibly allocate a local context.
-  if (info->scope()->num_heap_slots() > 0) {
+  if (info->scope()->NeedsContext()) {
     Comment cmnt(masm_, "[ Allocate context");
     // Argument to NewContext is the function, which is still in a1.
     bool need_write_barrier = true;
@@ -1207,7 +1207,7 @@ MemOperand FullCodeGenerator::ContextSlotOperandCheckExtensions(Variable* var,
   Register temp = t0;
 
   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".
         __ lw(temp, ContextMemOperand(context, Context::EXTENSION_INDEX));