Instead of passing around 6+ out-parameters, keep state inside the class.

No intended behavior change.

Bug: 570091
Change-Id: Ia15c1db2170680f0ec087b61f51af49e12fd7579
Reviewed-on: https://chromium-review.googlesource.com/561700
Commit-Queue: Paweł Hajdan Jr. <phajdan.jr@chromium.org>
Reviewed-by: Andrii Shyshkalov <tandrii@chromium.org>