Signal-Android/app/src/main/res/layout/sticker_view.xml

<?xml version="1.0" encoding="utf-8"?>
<merge
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    tools:parentTag="org.thoughtcrime.securesms.components.StickerView">

    <View
        android:id="@+id/sticker_missing_shade"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:background="?sticker_view_missing_background"
        android:visibility="gone"
        tools:visibility="visible"/>

    <org.thoughtcrime.securesms.components.ThumbnailView
        android:id="@+id/sticker_thumbnail"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:thumbnail_radius="0dp"
        app:thumbnail_fit="fit_center"/>

</merge>