Introduce ModuleScope subclass of DeclarationScope

src/ast/modules.cc

 // Copyright 2012 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 "src/ast/modules.h"
 #include "src/ast/ast-value-factory.h"
 #include "src/ast/scopes.h"
 
 namespace v8 {
 namespace internal {
@@ skipping 79 matching lines @@
       // Found an indirect export.
       DCHECK_NOT_NULL(it->second->module_request);
       DCHECK_NOT_NULL(it->second->import_name);
       entry->import_name = it->second->import_name;
       entry->module_request = it->second->module_request;
       entry->local_name = nullptr;
     }
   }
 }
 
-bool ModuleDescriptor::Validate(DeclarationScope* module_scope,
+bool ModuleDescriptor::Validate(ModuleScope* module_scope,
                                 PendingCompilationErrorHandler* error_handler,
                                 Zone* zone) {
-  DCHECK(module_scope->is_module_scope());
   DCHECK_EQ(this, module_scope->module());
   DCHECK_NOT_NULL(error_handler);
 
   // Report error iff there are duplicate exports.
   {
     ZoneAllocationPolicy allocator(zone);
     ZoneHashMap* export_names = new (zone->New(sizeof(ZoneHashMap)))
         ZoneHashMap(ZoneHashMap::PointersMatch,
                     ZoneHashMap::kDefaultHashMapCapacity, allocator);
     for (auto entry : exports_) {
@@ skipping 22 matching lines @@
       return false;
     }
   }
 
   MakeIndirectExportsExplicit();
   return true;
 }
 
 }  // namespace internal
 }  // namespace v8