This CL switches almost all instances of line tracking over to track
Positions instead. This does not yet add full range support - only the
start offsets will be correct currently. Followup CLs will extend the
ranges to fully cover their nodes.
Change-Id: Ie49aee02f35dcb30a3adb8a35f3e4914ba6939d2
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/518137
Reviewed-by: John Stiles <johnstiles@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: Ethan Nicholas <ethannicholas@google.com>
c9e9131f44