java/com/android/incallui/commontheme/res/animator/disabled_alpha.xml

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

  <item android:state_enabled="false">
    <set>
      <objectAnimator
        android:propertyName="alpha"
        android:duration="@android:integer/config_shortAnimTime"
        android:valueTo=".3f"
        android:valueType="floatType"/>
    </set>
  </item>
  <item>
    <set>
      <objectAnimator
        android:propertyName="alpha"
        android:duration="@android:integer/config_shortAnimTime"
        android:valueTo="1f"
        android:valueType="floatType"/>
    </set>
  </item>
</selector>