Enable FP reporting for PIP policy violations.

This queues a report through the Reporting API whenever
requestPictureInPicture is called in a frame in which the
'picture-in-picture' feature is not allowed according to feature policy.

Bug: 867471
Change-Id: I1cede10385f6a5110fd0ddd5bf124ff5d3737dd9
Reviewed-on: https://chromium-review.googlesource.com/c/1262432
Commit-Queue: Ian Clelland <iclelland@chromium.org>
Reviewed-by: François Beaufort <beaufort.francois@gmail.com>
Reviewed-by: Mounir Lamouri <mlamouri@chromium.org>
Cr-Commit-Position: refs/heads/master@{#596988}
4 files changed