Add kill switch for getDisplayMedia

getDisplayMedia() allows capturing user's display content. Before launching this
feature, we want to add a kill switch that can be set from server side in case
there exists some use case that causes security or privacy problems.

Bug: 326740
Change-Id: I34cf0cb412c599712fa10b0beb40b18404cf0440
Reviewed-on: https://chromium-review.googlesource.com/c/1313192
Commit-Queue: Emircan Uysaler <emircan@chromium.org>
Reviewed-by: Kentaro Hara <haraken@chromium.org>
Reviewed-by: Weiyong Yao <braveyao@chromium.org>
Reviewed-by: Philip Jägenstedt <foolip@chromium.org>
Reviewed-by: Guido Urdaneta <guidou@chromium.org>
Reviewed-by: Henrik Boström <hbos@chromium.org>
Cr-Commit-Position: refs/heads/master@{#610208}
6 files changed