[presubmit] Enable readability/namespace linter checking.

src/ic/stub-cache.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_STUB_CACHE_H_
 #define V8_STUB_CACHE_H_
 
 #include "src/macro-assembler.h"
 
 namespace v8 {
@@ skipping 147 matching lines @@
  private:
   Entry primary_[kPrimaryTableSize];
   Entry secondary_[kSecondaryTableSize];
   Isolate* isolate_;
 
   friend class Isolate;
   friend class SCTableReference;
 
   DISALLOW_COPY_AND_ASSIGN(StubCache);
 };
-}
-}  // namespace v8::internal
+}  // namespace internal
+}  // namespace v8
 
 #endif  // V8_STUB_CACHE_H_