[ui/vr] Add timeout for in-head permissions prompt.

Bug: 912759
Change-Id: I55b69f673d61a0ffa90127ea4e379407a7f9bf87
Reviewed-on: https://chromium-review.googlesource.com/c/1459325
Reviewed-by: Bill Orr <billorr@chromium.org>
Reviewed-by: Klaus Weidner <klausw@chromium.org>
Commit-Queue: Brian Sheedy <bsheedy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#630999}
2 files changed