[gold] Add a demo page for detail-list-sk.
[gold] Add a demo page for detail-list-sk.

Screenshot:
  https://screenshot.googleplex.com/jD0TCSwtGzN.png

Bug: skia:
Change-Id: I50e24853b865728db1ddae086098024aafdb49cb
Reviewed-on: https://skia-review.googlesource.com/99326
Reviewed-by: Stephan Altmueller <43343ec95731c0e8daa7359daf7f2f3935582b24@google.com>
Commit-Queue: Joe Gregorio <b9cf2471ff6d33504cafe8e6f356b732b2cadced@google.com>

google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot