In print preview, we already record and use whether the printed
document is modifiable to indicate whether the doc is html vs other
format like pdf. This CL records such info in print settings too
so that during print we can leverage such information. This is to
help print backend to know whether the printed document requires
composition for oopifs.

BUG=455764

Change-Id: I7b8524930a2c1cc2d7a6a78b49cfb0790710e82f
Reviewed-on: https://chromium-review.googlesource.com/696438


Commit-Queue: Wei Li <weili@chromium.org>
Reviewed-by: Lei Zhang <thestig@chromium.org>
Cr-Commit-Position: refs/heads/master@{#511607}