title: Modifier `protected` is not applicable inside `file` error in Kotlin
body: <p>I have a class whose declaration is like :</p>
  
  <pre><code>class NetworkManagerImpl : NetworkManager { }
  </code></pre>
  
  <p>I wanted to make the class protected so that it is visible inside package only. But when i add protected in front of class like :</p>
  
  <pre><code>protected class NetworkManagerImpl : NetworkManager { }
  </code></pre>
  
  <p>It gives error as <strong>Modifier <code>protected</code> is not applicable inside <code>file</code></strong>
  How to fix this error or more importantly how to make an entire class(Top level) protected?</p>