Add icon for anomaly preference

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

        android:width="24dp"

        android:height="24dp"

        android:viewportWidth="24.0"

        android:viewportHeight="24.0"

        android:tint="?android:attr/colorError">

    <path

        android:fillColor="#FF000000"

        android:pathData="M15.67,4L14,4L14,2h-4v2L8.33,4C7.6,4 7,4.6 7,5.33v15.33C7,21.4 7.6,22 8.33,22h7.33c0.74,0 1.34,-0.6 1.34,-1.33L17,5.33C17,4.6 16.4,4 15.67,4zM13,18h-2v-2h2v2zM13,14h-2L11,9h2v5z"/>

</vector>

    <Preference

        android:key="high_usage"

        android:icon="@drawable/ic_battery_alert_24dp"

        android:title="@string/power_high_usage_title"/>

    <PreferenceCategory