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During print preview when the PDF compositor is used, individual PDFs
for each page are made for the preview.  Prior art has the full
document PDF used for printing being generated by sending a separate
metafile blob for all the pages, which is overly large for long
documents.  This alters that to have the full document PDF get
composited using the same individual page metafile objects as they are
sent to the utility process for the composition.

This effectively halves the amount of IPC traffic for Skia metafile
data and eliminates potential huge metafile messages that can
overwhelm IPC limits.

This is only applicable for print preview scenarios that pass Skia
metafile into PDF compositor.  Non-modifiable content and basic
printing are unaffected in behavior.

This is a reland of https://crrev.com/c/1616461, which was reverted due
to a problem with death tests not detected with debug version of
components_unittests.

TBR=dcheng@chromium.org

Bug: 872935, 1024748
Change-Id: Ie22121c4bebae37882b3b2f6be808b8956c499ad
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1917685
Commit-Queue: Alan Screen <awscreen@chromium.org>
Reviewed-by: Lei Zhang <thestig@chromium.org>
Cr-Commit-Position: refs/heads/master@{#715570}