Embiggen the progress bar.

    <ProgressBar

        android:id="@+id/progressbar"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:layout_height="@dimen/progress_bar_height"

        android:indeterminate="true"

        style="@style/TrimmedHorizontalProgressBar"

        android:visibility="gone"/>

    <dimen name="root_icon_size">24dp</dimen>

    <dimen name="root_icon_margin">0dp</dimen>

    <dimen name="progress_bar_height">4dp</dimen>

    <dimen name="grid_width">152dp</dimen>

    <dimen name="grid_height">176dp</dimen>