[presubmit] Enable readability/namespace linter checking.

src/heap/scavenge-job.h

 // 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.
 
 #ifndef V8_HEAP_SCAVENGE_JOB_H_
 #define V8_HEAP_SCAVENGE_JOB_H_
 
 #include "src/cancelable-task.h"
 #include "src/heap/gc-tracer.h"
 
@@ skipping 56 matching lines @@
   static const size_t kMinAllocationLimit = 512 * KB;
   // The allocation limit cannot exceed this fraction of the new space capacity.
   static const double kMaxAllocationLimitAsFractionOfNewSpace;
 
  private:
   void ScheduleIdleTask(Heap* heap);
   bool idle_task_pending_;
   bool idle_task_rescheduled_;
   int bytes_allocated_since_the_last_task_;
 };
-}
-}  // namespace v8::internal
+}  // namespace internal
+}  // namespace v8
 
 #endif  // V8_HEAP_SCAVENGE_JOB_H_