packages/apps/Settings/res/xml/display_settings.xml
<!-- Hide screen sleep
<ListPreference
android:key="screen_timeout"
android:title="@string/screen_timeout"
android:summary="@string/screen_timeout_summary"
android:persistent="false"
android:entries="@array/screen_timeout_entries"
android:entryValues="@array/screen_timeout_values" /> --> packages/apps/Setting