Check system permission for video capture and fail with correct error on Mac.

* Fail with NotAllowedError, this consolidates with audio capture error.
* Trigger system dialog explicitly when authorization is not determined. This
  is needed so that the system gives the correct information when checking
  the authorization state later. Otherwise it incorrectly keeps returning
  "not determined" until browser restart.

Bug: 885184
Change-Id: I5c984e24877942f5924b172584d88974e5b9dd50
Reviewed-on: https://chromium-review.googlesource.com/c/1447732
Commit-Queue: Henrik Grunell <grunell@chromium.org>
Reviewed-by: Dominick Ng <dominickn@chromium.org>
Reviewed-by: Tommi <tommi@chromium.org>
Reviewed-by: Elly Fong-Jones <ellyjones@chromium.org>
Reviewed-by: Christian Fremerey <chfremer@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#628301}(cherry picked from commit f8fb175c085c0b523ea429204c759c427411a8bc)
Reviewed-on: https://chromium-review.googlesource.com/c/1451916
Reviewed-by: Henrik Grunell <grunell@chromium.org>
Cr-Commit-Position: refs/branch-heads/3683@{#153}
Cr-Branched-From: e51029943e0a38dd794b73caaf6373d5496ae783-refs/heads/master@{#625896}
3 files changed