Fix animation for the empty cabinet, also make other animations less jarring.

<com.android.documentsui.DirectoryView xmlns:android="http://schemas.android.com/apk/res/android"

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    android:orientation="vertical"

    android:animateLayoutChanges="true">

    android:orientation="vertical">

    <ProgressBar

        android:id="@+id/progressbar"

        android:layout_width="match_parent"

        android:layout_height="match_parent"

        android:orientation="vertical"

        android:background="@color/window_background"

        android:visibility="gone">

        <LinearLayout