[headless/devtools] Add option to ignore invalid pdf page ranges.

Bug: 603559
Change-Id: Ibabd53ccd478a767fcad05273b4ab11ee378b831
Reviewed-on: https://chromium-review.googlesource.com/571809
Reviewed-by: Pavel Feldman <pfeldman@chromium.org>
Reviewed-by: Alex Clarke <alexclarke@chromium.org>
Commit-Queue: Eric Seckler <eseckler@chromium.org>
Cr-Commit-Position: refs/heads/master@{#487821}
9 files changed