Includes "bear" samples from the Chromium project which include several
runs of PSSH boxes in their MOOF boxes.
MozReview-Commit-ID: 4KIJ2FCOyWT
--HG--
rename : dom/media/test/short-cenc.mp4 => dom/media/test/short-cenc-pssh-in-moof.mp4
extra : rebase_source : 29cd7ea0e3b76935d76e376ee0f88f4c93aca85d