Made position parameter of DSL ReportErrors required

This adds line numbers to a bunch of errors which were previously
missing them.

Change-Id: Id77c08d168b0a2d8a0131a53aa004bf37b8bec02
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/444176
Commit-Queue: Ethan Nicholas <ethannicholas@google.com>
Reviewed-by: John Stiles <johnstiles@google.com>
6 files changed