Hybrid Hotseat a11y

- speak meaningful accessibility label for predicted items
- disable accessibility focus for on-boarding preview items
- add PIN as an accessibility action
- remove move and remove actions for prediction icons

Bug:152376193
Bug:152359303
Bug:152374583
Bug:152357657
Bug:152268303
Bug:152379490

Change-Id: I40fe0ef6329cd5b1d9215ac5fa1716f15db89ac8