Add boolean to tell if V8 zaps allocated memory

src/api.cc

Index: src/api.cc
diff --git a/src/api.cc b/src/api.cc
index ba8de1cc9c70aee427f8566dfd884c3eae736619..7d15afb0e2e152fddea413b90c2141fb5a3d27f9 100644
--- a/src/api.cc
+++ b/src/api.cc
@@ -7173,6 +7173,7 @@ void Isolate::GetHeapStatistics(HeapStatistics* heap_statistics) {
   heap_statistics->total_available_size_ = heap->Available();
   heap_statistics->used_heap_size_ = heap->SizeOfObjects();
   heap_statistics->heap_size_limit_ = heap->MaxReserved();
+  heap_statistics->did_zap_garbage_ = heap->ShouldZapGarbage();
 }