[SB][Notifs] Fade out end of status bar notif chip text, don't ellipsize

To leave as much room as possible for text in the status bar, we don't
want to ellipsize the text if it doesn't fit because the ... takes up a
lot of room. Instead, just fade out the end.

Bug: 364653005
Flag: com.android.systemui.status_bar_notification_chips
Test: Manual, see screenshot in bug
Change-Id: I095665a171b8276ca5724304b5dabb6c45c7b6e8