GitLab

Looks like this crash is happening right when the browser starts in some
weird corner case. This CL just exists early if web_contents() is null.

Bug: 876835
Change-Id: I6dc7eecbd42becb077d9156a28974264c4c90166
Reviewed-on: https://chromium-review.googlesource.com/1185898Reviewed-by: Ryan Sturm <ryansturm@chromium.org>
Commit-Queue: Robert Ogden <robertogden@chromium.org>
Cr-Commit-Position: refs/heads/master@{#585377}