[presubmit] Enable readability/namespace linter checking.

src/ast-literal-reindexer.cc

 // Copyright 2015 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-literal-reindexer.h"
 
 #include "src/ast.h"
 #include "src/scopes.h"
 
 namespace v8 {
@@ skipping 298 matching lines @@
 
 
 void AstLiteralReindexer::VisitFunctionLiteral(FunctionLiteral* node) {
   // We don't recurse into the declarations or body of the function literal:
 }
 
 
 void AstLiteralReindexer::Reindex(Expression* pattern) {
   pattern->Accept(this);
 }
-}
-}  // namespace v8::internal
+}  // namespace internal
+}  // namespace v8