Prevent accounts page directly opening in screen pinning mode

In Settings there is no auth mechanism to prevent accounts page being
opened in screen pinning mode. This CL makes it so that when users are
trying to navigate to any pages in Settings from other apps in screen
pinning mode, Settings app will directly close its page.

Bug: 137015265
Test: manual
Change-Id: Ice2250eb00be9d2181901cef6d1f04b4a8233bfc