Merge "Fix sketchy usage of new PreferenceScreen" into oc-dev

<?xml version="1.0" encoding="utf-8"?>

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  Copyright (C) 2017 The Android Open Source Project

  Licensed under the Apache License, Version 2.0 (the "License");

  you may not use this file except in compliance with the License.

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<PreferenceScreen />

        mUnavailable = isUiRestricted();

        setHasOptionsMenu(!mUnavailable);

        if (mUnavailable) {

            setPreferenceScreen(new PreferenceScreen(getPrefContext(), null));

            getPreferenceScreen().removeAll();

            addPreferencesFromResource(R.xml.empty_settings);

            return;

        }

            // Block access to developer options if the user is not the owner, if user policy

            // restricts it, or if the device has not been provisioned

            mUnavailable = true;

            setPreferenceScreen(new PreferenceScreen(getPrefContext(), null));

            addPreferencesFromResource(R.xml.empty_settings);

            return;

        }