Print Preview Componentization: Add tests and update pages

Print ticket expects the pages to be sent in the format of an array
with from and to fields in each element, or a null pointer/empty array
if the full range is to be printed. Change pages value to this format
and add a test.

Bug: 773928
Cq-Include-Trybots: master.tryserver.chromium.linux:closure_compilation
Change-Id: I5087d958e2cb5f60789053d7f152d5dfbe5b6617
Commit-Queue: Rebekah Potter <>
Reviewed-by: Demetrios Papadopoulos <>
Cr-Commit-Position: refs/heads/master@{#528370}
3 files changed