LockPatternUtils: isSecure: respect profile settings

When the lock screen is set to secure and overridden to insecure
by profile settings, isSecure() would return true causing confusion
to some code.

For example, attempting to use a lockscreen shortcut
to launch an activity will cause the device to soft-reboot due to
recursive calling and a stack overflow.

Change-Id: I02984671c2a047765f4da1f6a44bb19dea5bf2d3
Profile: respect DPM when overriding screen lock (1/2)

Profile currently allows the user to override the keyguard set by
device policy, which is undesired.

Change-Id: Id8d80cfdad51ca0a64dc231a77e53b104ecb9825