Add an overlay for photo preview

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

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<!-- empty stub -->

<merge />

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        <include layout="@layout/ambient_indication"

            android:id="@+id/ambient_indication_container" />

        <include layout="@layout/photo_preview_overlay" />

        <ViewStub

            android:id="@+id/keyguard_user_switcher"

            android:layout="@layout/keyguard_user_switcher"