actionbar_group_icon.xml

<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">

    <item
        android:drawable="@drawable/ic_group"
        android:gravity="center" /> 
  
    <item
        android:id="@+id/ic_group_count"
        android:drawable="@color/transparent" />

</layer-list>