[presubmit] Enable readability/namespace linter checking.

src/x87/codegen-x87.h

 // 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.
 
 #ifndef V8_X87_CODEGEN_X87_H_
 #define V8_X87_CODEGEN_X87_H_
 
 #include "src/ast.h"
 #include "src/macro-assembler.h"
 
@@ skipping 10 matching lines @@
                        Factory* factory,
                        Register string,
                        Register index,
                        Register result,
                        Label* call_runtime);
 
  private:
   DISALLOW_COPY_AND_ASSIGN(StringCharLoadGenerator);
 };
 
-} }  // namespace v8::internal
+}  // namespace internal
+}  // namespace v8
 
 #endif  // V8_X87_CODEGEN_X87_H_