Always place notification dots directly on adaptive icon path

- Calculate point on icon path nearest to top right corner, and
  use that as center for the dot
- Cleanup code related to dot offset

Test:
Set each style (different icon shape) and verify dot is in correct
placement for each of:
- Folders
- Icons in folders
- Icons in all apps
- Icons on workspace

Bug: 124414511
Change-Id: I036ed3677e8af222f00d4fad4a36a7e4d9b49ad9