[presubmit] Enable readability/namespace linter checking.

src/scopes.h

 // 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.
 
 #ifndef V8_SCOPES_H_
 #define V8_SCOPES_H_
 
 #include "src/ast.h"
 #include "src/pending-compilation-error-handler.h"
 #include "src/zone.h"
@@ skipping 803 matching lines @@
   AstValueFactory* ast_value_factory_;
   Zone* zone_;
 
   PendingCompilationErrorHandler pending_error_handler_;
 
   // For tracking which classes are declared consecutively. Needed for strong
   // mode.
   int class_declaration_group_start_;
 };
 
-} }  // namespace v8::internal
+}  // namespace internal
+}  // namespace v8
 
 #endif  // V8_SCOPES_H_