Add some extra info to dumpsys for bubble bar expanded view

- TaskView / ExpandedView alpha /visibility state

Bug: 438501901
Test: adb shell dumpsys activity service com.android.systemui | grep -A 100 BubbleController
Flag: EXEMPT trivial logs addition
Change-Id: Ia6a7ff393722dc5faa67c15cc282d2b61fbd1221