title: Android close DrawerLayout when it is on Lock mode
body: <p>when i set lock and disable swipe on open and close drawer layout i cant close that by pressing on back button on the phone, when mode is not lock pressing back button cause of close that but when i change mode to for example :</p>
  
  <pre><code>drawer_layout.setDrawerLockMode(DrawerLayout.LOCK_MODE_LOCKED_CLOSED);
  </code></pre>
  
  <p>pressing back button couldn't close that</p>