Remove unnecessary paint invalidation diff.

LayoutObject::SetStyle() with existing style_ == nullptr means the
LayoutObject has just been created and about to be inserted into the
layout tree. Any invalidation of layout, paint, etc will be handled by
the layout tree insertion code and the following layout.

Bug: 817610
Change-Id: I75bff88c26037f662c1e3250e703d0920e34e46a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1517706
Reviewed-by: Chris Harrelson <chrishtr@chromium.org>
Commit-Queue: Rune Lillesveen <futhark@chromium.org>
Cr-Commit-Position: refs/heads/master@{#640101}
1 file changed