title: Does android:exported="false" restrict system calls/access?
body: <p>I know that setting android:exported="false" will restrict other applications from using/accessing my application components.<br>
  Does setting this attribute will restrict the system as well from using/accessing my components? i doubt.   </p>
  
  <p>for example, i have the following receiver:    </p>
  
  <pre><code>   &lt;receiver
          android:name="ConnectivityManager"
          android:label="NetworkConnection"
          android:exported = "false" &gt;
          &lt;intent-filter&gt;
              &lt;action android:name="android.net.conn.CONNECTIVITY_CHANGE" /&gt;
          &lt;/intent-filter&gt;
      &lt;/receiver&gt;
  </code></pre>
  
  <p>The receiver is still receiving broadcasts from the system once the connection state changes (on/of).   </p>
  
  <p>Does this mean that the system calls/access can never be stopped? Please illustrate.</p>