Add a mode to completely deserialize scope chains

src/ast/scopes.h

Index: src/ast/scopes.h
diff --git a/src/ast/scopes.h b/src/ast/scopes.h
index d8edf9148fe91a6cbc5221b095eee599962017cc..645fdad347ae28dee6900b83f4a18a821bd5e988 100644
--- a/src/ast/scopes.h
+++ b/src/ast/scopes.h
@@ -114,9 +114,12 @@ class Scope: public ZoneObject {
   // doesn't re-allocate variables repeatedly.
   static bool Analyze(ParseInfo* info);
 
+  enum class DeserializationMode { kDeserializeOffHeap, kKeepScopeInfo };
+
   static Scope* DeserializeScopeChain(Isolate* isolate, Zone* zone,
                                       Context* context, Scope* script_scope,
-                                      AstValueFactory* ast_value_factory);
+                                      AstValueFactory* ast_value_factory,
+                                      DeserializationMode deserialization_mode);
 
   // The scope name is only used for printing/debugging.
   void SetScopeName(const AstRawString* scope_name) {
@@ -851,6 +854,9 @@ class Scope: public ZoneObject {
 
   void SetDefaults();
 
+  void DeserializeScopeInfo(Isolate* isolate,
+                            AstValueFactory* ast_value_factory);
+
   PendingCompilationErrorHandler pending_error_handler_;
 };