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

test/cctest/test-types.cc

Index: test/cctest/test-types.cc
diff --git a/test/cctest/test-types.cc b/test/cctest/test-types.cc
index d2e1c2588442d6c4dd209d2a7f9610bc75d34bf0..7b7706febf6c5107420ac009b8ceeb5ccfe17848 100644
--- a/test/cctest/test-types.cc
+++ b/test/cctest/test-types.cc
@@ -40,7 +40,7 @@ struct Tests {
   Tests()
       : isolate(CcTest::InitIsolateOnce()),
         scope(isolate),
-        zone(),
+        zone(isolate->allocator()),
         T(&zone, isolate, isolate->random_number_generator()) {}
 
   bool IsBitset(Type* type) { return type->IsBitsetForTesting(); }