GitLab

- Use range-based for loops.
- Add a GetPrintPreviewUIForDialog() helper function.

Change-Id: Ib571f575d53f8f8b6ad857e61f2b1111cf2ab5a1
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1497857
Commit-Queue: Lei Zhang <thestig@chromium.org>
Reviewed-by: Rebekah Potter <rbpotter@chromium.org>
Cr-Commit-Position: refs/heads/master@{#637934}