Revert "Remove scroll offset rounding in position:sticky"

This reverts commit 7fa81dd1d86eda43b689a74a4099251b56a29f60. The commit
incorrectly handled sticky position offsets in non-LTR containers
resulting in a mismatch between the composited sticky position and the
main thread position making it impossible to click on content in these boxes.

[email protected]

Bug: 1050348,1010961
Change-Id: I62b230416148a2cd905c79da867fd44beeb5b53d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2047443
Reviewed-by: Robert Flack <[email protected]>
Commit-Queue: Robert Flack <[email protected]>
Cr-Commit-Position: refs/heads/master@{#739929}
2 files changed