[LayoutNG] Position descendants in inline containing block.

Part 4 of 4 of inline containing block for OOF descendants
https://chromium-review.googlesource.com/c/chromium/src/+/777707

Geometry of computing the containing block coordinates is complex.

In the old code, all containing block geometry was stored as members of
NGOutOfFlowLayoutPart.

With inline containing blocks, each inline-cb can have a different geometry.
Code was refactored so that cb geometry is configurable per descendant.

Bug: 740993
Change-Id: I3dd392472081ac6b09dd6a2540d142ba9966f3a6
Reviewed-on: https://chromium-review.googlesource.com/818333
Commit-Queue: Aleks Totic <atotic@chromium.org>
Reviewed-by: Koji Ishii <kojii@chromium.org>
Cr-Commit-Position: refs/heads/master@{#523635}
3 files changed