java/com/android/dialer/theme/res/drawable/front_back_switch_button_animation.xml

<?xml version="1.0" encoding="utf-8"?>
<animated-vector
  xmlns:android="http://schemas.android.com/apk/res/android"
  android:drawable="@drawable/front_back_switch_button">
  <target
    android:name="layer_10_outlines"
    android:animation="@anim/front_back_switch_button_animation"/>
</animated-vector>