Reland "Recompute overflow after transform changes"

This CL adds a special code path that is very similar to simplifiedLayout.
When the only change on an element is the transform, we can do the minimal
work to recompute the layout overflow without much overhead from layout.

This is done by adding an overflow recalculation phase after style changes,
if a RenderObject doesn't need layout and has moved transformed children,
the special code path will kick in.

BUG=352460

Review URL: https://codereview.chromium.org/250773002

git-svn-id: svn://svn.chromium.org/blink/trunk@172833 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Web Animations API: Element.animate should accept a null effect

Review URL: https://codereview.chromium.org/254423004

git-svn-id: svn://svn.chromium.org/blink/trunk@172834 bbb929c8-8fbe-4397-9dbb-9b2b20218538