Sandra, all the spec changes are merged. Are you still working on making this change in Chrome as well?

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/688cba0e79b7e2e7de8c0334556956557afc675f

commit 688cba0e79b7e2e7de8c0334556956557afc675f
Author: Sandra Sun <sunyunjia@chromium.org>
Date: Tue Jan 22 15:23:03 2019

Change defaults for ScrollIntoViewOptions to start/nearest.

This patch changes the defaults for ScrollIntoView Options from
center/center to start/nearest to match the spec.
https://drafts.csswg.org/cssom-view/#extension-to-the-element-interface

Bug:  764282 
Change-Id: If6616039cc0eb523e7b2dac530c81857e486cffb
Reviewed-on: https://chromium-review.googlesource.com/c/1425858
Reviewed-by: David Bokan <bokan@chromium.org>
Commit-Queue: Sandra Sun <sunyunjia@chromium.org>
Cr-Commit-Position: refs/heads/master@{#624784}
[modify] https://crrev.com/688cba0e79b7e2e7de8c0334556956557afc675f/third_party/blink/renderer/core/frame/scroll_into_view_options.idl
[delete] https://crrev.com/e0214115425987eec543712670784fb758c4cbe5/third_party/blink/web_tests/external/wpt/css/cssom-view/scrollintoview-expected.txt