Expose a lower bound of malloc'd memory via heap statistics

src/code-stubs.cc

Index: src/code-stubs.cc
diff --git a/src/code-stubs.cc b/src/code-stubs.cc
index 7ac1eb30ac0474f8985ffa02ef4102b254c68e12..d0cb7939a62ff5d805aa9d8ecba17310092888ed 100644
--- a/src/code-stubs.cc
+++ b/src/code-stubs.cc
@@ -455,7 +455,7 @@ void CompareICStub::Generate(MacroAssembler* masm) {
 
 Handle<Code> TurboFanCodeStub::GenerateCode() {
   const char* name = CodeStub::MajorName(MajorKey());
-  Zone zone;
+  Zone zone(isolate()->allocator());
   CallInterfaceDescriptor descriptor(GetCallInterfaceDescriptor());
   compiler::CodeStubAssembler assembler(isolate(), &zone, descriptor,
                                         GetCodeFlags(), name);