Fix abspos DCHECK crash

Bug: 740993
Cq-Include-Trybots: master.tryserver.chromium.linux:linux_layout_tests_layout_ng
Change-Id: I88816900bd0b55b6b6d8c5b139a2819ebfa1a9a3
Reviewed-on: https://chromium-review.googlesource.com/963510
Reviewed-by: Ian Kilpatrick <ikilpatrick@chromium.org>
Commit-Queue: Aleks Totic <atotic@chromium.org>
Cr-Commit-Position: refs/heads/master@{#543236}
2 files changed