GitLab

ParentDocument() can be nullptr.

Bug: 750836
Change-Id: Idff5feeececa8ad32f3248c565c878902dd24ffc
Reviewed-on: https://chromium-review.googlesource.com/597370
Commit-Queue: Kent Tamura <tkent@chromium.org>
Reviewed-by: Hayato Ito <hayato@chromium.org>
Cr-Commit-Position: refs/heads/master@{#491277}