[presubmit] Enable readability/namespace linter checking.

src/heap/array-buffer-tracker.h

Index: src/heap/array-buffer-tracker.h
diff --git a/src/heap/array-buffer-tracker.h b/src/heap/array-buffer-tracker.h
index c12557a9fceb6e229a27c0b67dc78a504f0b4075..7ba22fb57328a9b42a9aedda7512afe9d9c15cf2 100644
--- a/src/heap/array-buffer-tracker.h
+++ b/src/heap/array-buffer-tracker.h
@@ -68,6 +68,6 @@ class ArrayBufferTracker {
   std::map<void*, size_t> live_array_buffers_for_scavenge_;
   std::map<void*, size_t> not_yet_discovered_array_buffers_for_scavenge_;
 };
-}
-}  // namespace v8::internal
+}  // namespace internal
+}  // namespace v8
 #endif  // V8_HEAP_ARRAY_BUFFER_TRACKER_H_