Update point dimensions and also dash gap per UX spec.

Point: 12dp x 12dp, with 2dp corner radius.
  - down from 20dp x 20dp, 4dp corner radius.
Segment point gap: 8dp.
  - down from 4dp.
Dash gap: 8dp.
  - from 9dp.

Flag: android.app.api_rich_ongoing
Fix: 376266032
Fix: 376265307
Test: post a ProgressStyle notification with points.
Change-Id: Id0e52e018bc00e3e8d45bc4e84bf3bd35d3f6e5a