Fix cpplint whitespace/blank_line issues

Change-Id: Ice937e95e23dd622c17054551d4ae4cebd0ef8a2
diff --git a/runtime/atomic_integer.h b/runtime/atomic_integer.h
index 117e837..6711722 100644
--- a/runtime/atomic_integer.h
+++ b/runtime/atomic_integer.h
@@ -70,10 +70,11 @@
     bool success = android_atomic_cas(expected_value, new_value, &value_) == 0;
     return success;
   }
+
  private:
   volatile int32_t value_;
 };
 
-}
+}  // namespace art
 
 #endif  // ART_RUNTIME_ATOMIC_INTEGER_H_