Restriction pin changes.

Fixed bug in WirelessSettings where it was asking users for a PIN when
they weren't restricted.  Did this by refactoring the preference level
pin checking into the superclass, where it checks for the restricted mode first.
Also pin protected changes to certificates for restricted users.

Change-Id: I8310fd39f0862159668318fc1360ec6859cc00d5

src/com/android/settings/SettingsPreferenceFragment.java

@@ -241,7 +241,7 @@ public class SettingsPreferenceFragment extends PreferenceFragment implements Di
                     mParentFragment = getFragmentManager().findFragmentById(mParentFragmentId);
                     if (!(mParentFragment instanceof DialogCreatable)) {
                         throw new IllegalArgumentException(
-                                (mParentFragment != null 
+                                (mParentFragment != null
                                         ? mParentFragment.getClass().getName()
                                         : mParentFragmentId)
                                 + " must implement "