Restrict the xss audit report URL to same origin

BUG=441275
R=tsepez@chromium.org,mkwst@chromium.org

Change-Id: I27bc8e251b9ad962c3b4fdebf084a2b9152f915d
Reviewed-on: https://chromium-review.googlesource.com/768367
Reviewed-by: Tom Sepez <tsepez@chromium.org>
Reviewed-by: Mike West <mkwst@chromium.org>
Commit-Queue: Jochen Eisinger <jochen@chromium.org>
Cr-Commit-Position: refs/heads/master@{#516666}
4 files changed