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When using a PrintRenderer, preview documents are rendered
asynchronously, and mulitiple preview document requests may be issued
before a preview document is returned. If the returned preview
document's cookie does not match the latest document cookie, ignore it
and wait for the final preview document.

Bug: b:144448724
Test: Print from an ARC app and rapidly change print settings
Change-Id: I2b705abd5c86f3b2e54151d07a4c48201560e320
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1914831Reviewed-by: Lei Zhang <thestig@chromium.org>
Commit-Queue: Jesse Schettler <jschettler@chromium.org>
Cr-Commit-Position: refs/heads/master@{#715276}