Fix repeating apps on pause/resume

Preference list was getting duplicated on pausing and resuming the activity.

Pull the user info out of the preference list and make it a static header
so that it stays fixed. Can now remove all entries before re-adding.

Disable location by default and disable ability to change Unknown sources
 toggle.

Bug: 8685561
Bug: 8688400

Change-Id: I64ce728d5369e03ddaba562bcd66bb0720a037d2

src/com/android/settings/SecuritySettings.java

@@ -257,10 +257,8 @@ public class SecuritySettings extends SettingsPreferenceFragment
                 KEY_TOGGLE_INSTALL_APPLICATIONS);
         mToggleAppInstallation.setChecked(isNonMarketAppsAllowed());
 
-        boolean isSideloadingAllowed =
-                !um.hasUserRestriction(UserManager.DISALLOW_INSTALL_UNKNOWN_SOURCES);
         // Side loading of apps.
-        mToggleAppInstallation.setEnabled(isSideloadingAllowed);
+        mToggleAppInstallation.setEnabled(mIsPrimary);
 
         // Package verification, only visible to primary user and if enabled
         mToggleVerifyApps = (CheckBoxPreference) findPreference(KEY_TOGGLE_VERIFY_APPLICATIONS);