Move activeCues ownership to TextTrack

Instead of having a list that owns another list (that owns another
list...), move the m_activeCues member from TextTrackCueList to TextTrack.
This is structurally less strange, and makes TextTrackCueList slightly
more self-contained. The code for building the activeCues list remains
(for now.)

BUG=321654

Review URL: https://codereview.chromium.org/958903002

git-svn-id: svn://svn.chromium.org/blink/trunk@190923 bbb929c8-8fbe-4397-9dbb-9b2b20218538
4 files changed
tree: deaef14a569505dfbbeb5d8e8fc2e24a1badf6fd
  1. third_party/