Fix arrow functions requiring context without slots.

src/compiler/ast-graph-builder.cc

Index: src/compiler/ast-graph-builder.cc
diff --git a/src/compiler/ast-graph-builder.cc b/src/compiler/ast-graph-builder.cc
index 247f674981c6892183424c8da7f22bdf43d854c3..75d299ba649c68e8b3c9e0c49c3048c4160c122b 100644
--- a/src/compiler/ast-graph-builder.cc
+++ b/src/compiler/ast-graph-builder.cc
@@ -525,8 +525,7 @@ bool AstGraphBuilder::CreateGraph(bool constant_context, bool stack_check) {
   }
 
   // Build function context only if there are context allocated variables.
-  int heap_slots = info()->num_heap_slots() - Context::MIN_CONTEXT_SLOTS;
-  if (heap_slots > 0) {
+  if (info()->num_heap_slots() > 0) {
     // Push a new inner context scope for the function.
     Node* inner_context =
         BuildLocalFunctionContext(function_context_.get(), patched_receiver);