[presubmit] Enable readability/namespace linter checking.

src/context-measure.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/context-measure.h"
 
 #include "src/base/logging.h"
 #include "src/contexts.h"
 #include "src/objects-inl.h"
 
@@ skipping 56 matching lines @@
   object->IterateBody(map->instance_type(), size, this);
 }
 
 
 void ContextMeasure::VisitPointers(Object** start, Object** end) {
   for (Object** current = start; current < end; current++) {
     if ((*current)->IsSmi()) continue;
     MeasureObject(HeapObject::cast(*current));
   }
 }
-}
-}  // namespace v8::internal
+}  // namespace internal
+}  // namespace v8