Introduce NewScriptScope that creates a top-level scope

src/parsing/preparser.cc

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <cmath>
 
 #include "src/allocation.h"
 #include "src/base/logging.h"
 #include "src/conversions-inl.h"
 #include "src/conversions.h"
@@ skipping 113 matching lines @@
 
 PreParser::PreParseResult PreParser::PreParseLazyFunction(
     LanguageMode language_mode, FunctionKind kind, bool has_simple_parameters,
     bool parsing_module, ParserRecorder* log, Scanner::BookmarkScope* bookmark,
     int* use_counts) {
   parsing_module_ = parsing_module;
   log_ = log;
   use_counts_ = use_counts;
   // Lazy functions always have trivial outer scopes (no with/catch scopes).
   DCHECK_NULL(scope_state_);
-  Scope* top_scope = NewScope(nullptr, SCRIPT_SCOPE);
+  Scope* top_scope = NewScriptScope();
   PreParserFactory top_factory(nullptr);
   FunctionState top_state(&function_state_, &scope_state_, top_scope,
                           kNormalFunction, &top_factory);
   scope()->SetLanguageMode(language_mode);
   Scope* function_scope = NewFunctionScope(kind);
   if (!has_simple_parameters) function_scope->SetHasNonSimpleParameters();
   PreParserFactory function_factory(nullptr);
   FunctionState function_state(&function_state_, &scope_state_, function_scope,
                                kind, &function_factory);
   DCHECK_EQ(Token::LBRACE, scanner()->current_token());
@@ skipping 1176 matching lines @@
 
   body->Add(PreParserStatement::ExpressionStatement(return_value), zone());
 }
 
 #undef CHECK_OK
 #undef CHECK_OK_CUSTOM
 
 
 }  // namespace internal
 }  // namespace v8