Fix updating icons with BigPictureIconManager after reinflating the layout

Whenever a new layout is inflated for a BigPictureStyle Notification,
the BigPictureIconManager gets updated with a new DrawableConsumer. The
previous code wasn't following up on those updates.

Fixes: 306369469
Test: atest BigPictureIconManagerTest
Test: observe BigPictureStyle Notifications after theme changes
and updates
Flag: statusbar flag bigpicture_notification_lazy_loading

Change-Id: If7de5ab2a88e422ffbb6fb41fb33462a351b1a98