Allow embedders to pass a font manager.
In order to avoid excessive factory API clutter, introduce an
Animation::Builder helper to wrap factory options.
Also clean up various bits:
* hoist scene parsing out of the Animation ctor
* store the animation duration explicitly (instead of unused fps)
* plumb const SkFontMgr& internally (instead of a ref)
Change-Id: I3e180dfa85ba18c8462cfeb5a7385bef985ed6c4
Reviewed-on: https://skia-review.googlesource.com/148800
Reviewed-by: Ben Wagner <bungeman@google.com>
Commit-Queue: Florin Malita <fmalita@chromium.org>
40c37426b3