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In CompositeAfterPaint, though backface-visibility:hidden doesn't
directly cause compositing, it's very likely that we'll composite the
element (when we find its backface-visibility is different from the
previous paint chunk), and it indicates preference of compositing, so
it's mostly beneficial to prepare for compositing in paint properties:
- by creating PaintOffsetTranslation to avoid raster invalidation on
  paint offset change;
- by preferring composited scrolling.

Change-Id: I57a59d17a3e864416c479d788291f3a201644c10
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2121355Reviewed-by: Stefan Zager <szager@chromium.org>
Commit-Queue: Xianzhu Wang <wangxianzhu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#753799}