Notify content capture on detach before setting attachInfo to null.

If a view is detached before being removed (which seems common with some
recycler list views) then no content capture view removed event is sent
(notifyAppearedOrDisappearedForContentCaptureIfNeeded does nothing
if mAttachInfo is null).

Fix: 200166989
Test: Manual verification using AiAi logging
Change-Id: Ic04af005bb4ad425ba8398439f1f47bb6bcb334c