Reland "Another fix for dash line thickness."

This is a reland of bf1904fd4898bb0f73f05e890b88a3ffc6acc064

Fix for case of scaling matrix and update GM to use a scaling
matrix.

Original change's description:
> Another fix for dash line thickness.
>
> Use the device space offset from the dash centerline for
> antialiasing in y direction.
>
> Bug: chromium:1049028
>
> Change-Id: Ib6363579680d05cbf1fe34795695422baeca7065
> Reviewed-on: https://skia-review.googlesource.com/c/skia/+/288764
> Reviewed-by: Greg Daniel <egdaniel@google.com>
> Commit-Queue: Brian Salomon <bsalomon@google.com>

Bug: chromium:1049028
Change-Id: I6d2b04f9cf5de302c41045c2e2494cee43092d9a
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/288976
Reviewed-by: Greg Daniel <egdaniel@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>
2 files changed