Track ascii-ness of data in externalized strings.

src/heap.h

Index: src/heap.h
diff --git a/src/heap.h b/src/heap.h
index 0db40083feecd465893ef17482265b0300ebabf6..92c817c3a95af2baba20002aa4995b5923630c69 100644
--- a/src/heap.h
+++ b/src/heap.h
@@ -69,10 +69,12 @@ class ZoneScopeInfo;
   V(Map, cons_symbol_map, ConsSymbolMap)                                       \
   V(Map, cons_ascii_symbol_map, ConsAsciiSymbolMap)                            \
   V(Map, external_symbol_map, ExternalSymbolMap)                               \
+  V(Map, external_symbol_with_ascii_data_map, ExternalSymbolWithAsciiDataMap)  \
   V(Map, external_ascii_symbol_map, ExternalAsciiSymbolMap)                    \
   V(Map, cons_string_map, ConsStringMap)                                       \
   V(Map, cons_ascii_string_map, ConsAsciiStringMap)                            \
   V(Map, external_string_map, ExternalStringMap)                               \
+  V(Map, external_string_with_ascii_data_map, ExternalStringWithAsciiDataMap)  \
   V(Map, external_ascii_string_map, ExternalAsciiStringMap)                    \
   V(Map, undetectable_string_map, UndetectableStringMap)                       \
   V(Map, undetectable_ascii_string_map, UndetectableAsciiStringMap)            \