Show notification about auto-selected layout when PK connected

Only 1 layout selected: https://screenshot.googleplex.com/4xxrBhEWv6VM7gD
2 Layouts selected: https://screenshot.googleplex.com/63qufkk6hjZR56q
3 layouts selected: https://screenshot.googleplex.com/pzXSX6bVTQdsSwJ
4 or more layouts selected: https://screenshot.googleplex.com/57W8H9AWwHA7VGs
Missing layout: https://screenshot.googleplex.com/8A8boZCU9E43zSi

Test: manual
Bug: 259530132
Change-Id: I1471eba1514688cab6dcedd10db93a39fcea4bf2