[presubmit] Enable readability/namespace linter checking.

test/cctest/compiler/c-signature.h

Index: test/cctest/compiler/c-signature.h
diff --git a/test/cctest/compiler/c-signature.h b/test/cctest/compiler/c-signature.h
index 8eaf6325f22011081d6a6a957440c66aae44248d..6a17a29856b421254b18ae1c416ad72ff45849c7 100644
--- a/test/cctest/compiler/c-signature.h
+++ b/test/cctest/compiler/c-signature.h
@@ -159,8 +159,8 @@ typedef CSignature2<uint32_t, uint32_t, uint32_t> CSignature_u_uu;
 typedef CSignature2<float, float, float> CSignature_f_ff;
 typedef CSignature2<double, double, double> CSignature_d_dd;
 typedef CSignature2<Object*, Object*, Object*> CSignature_o_oo;
-}
-}
-}  // namespace v8::internal::compiler
+}  // namespace compiler
+}  // namespace internal
+}  // namespace v8
 
 #endif  // V8_COMPILER_C_SIGNATURE_H_