[async-iteration] expose Symbol.asyncIterator behind flag --harmony-async-iteration

src/heap-symbols.h

Index: src/heap-symbols.h
diff --git a/src/heap-symbols.h b/src/heap-symbols.h
index cf8739167e7e1e252d1344747f714454b62febdc..4b55b50edfb7f798ce6eece92d633184c232cc43 100644
--- a/src/heap-symbols.h
+++ b/src/heap-symbols.h
@@ -242,15 +242,16 @@
   V(strict_function_transition_symbol) \
   V(uninitialized_symbol)
 
-#define PUBLIC_SYMBOL_LIST(V)                \
-  V(iterator_symbol, Symbol.iterator)        \
-  V(intl_fallback_symbol, IntlFallback)      \
-  V(match_symbol, Symbol.match)              \
-  V(replace_symbol, Symbol.replace)          \
-  V(search_symbol, Symbol.search)            \
-  V(species_symbol, Symbol.species)          \
-  V(split_symbol, Symbol.split)              \
-  V(to_primitive_symbol, Symbol.toPrimitive) \
+#define PUBLIC_SYMBOL_LIST(V)                    \
+  V(async_iterator_symbol, Symbol.asyncIterator) \
+  V(iterator_symbol, Symbol.iterator)            \
+  V(intl_fallback_symbol, IntlFallback)          \
+  V(match_symbol, Symbol.match)                  \
+  V(replace_symbol, Symbol.replace)              \
+  V(search_symbol, Symbol.search)                \
+  V(species_symbol, Symbol.species)              \
+  V(split_symbol, Symbol.split)                  \
+  V(to_primitive_symbol, Symbol.toPrimitive)     \
   V(unscopables_symbol, Symbol.unscopables)
 
 // Well-Known Symbols are "Public" symbols, which have a bit set which causes