o which would not
be detected by Angular&#39;s change detector and thus not trigger <code>$onChanges</code>. This hook is invoked with no arguments;
if detecting changes, you must store the previous value(s) for comparison to the current values.</li>
<li><code>$onDestroy()</code> - Called on a controller when its containing scope is destroyed. Use this hook for releasing
external resources, watches and event handlers. Note that components have their <code>$onDestroy()</code> hooks called in
the same order a