Expose SkFaceRec less.

Expose SkFaceRec less.

The SkFaceRec class is some data which needs to remain alive for the
life of an FT_Face. ref_ft_face returns SkFaceRec, but confusingly
unref_ft_face takes an FT_Face. Since no one was using the SkFaceRec
for anything other than accessing the FT_Face, have ref_ft_face
return FT_Face instead and remove the unused SkFaceRec pointer from
the scaler context.

Committed: https://skia.googlesource.com/skia/+/13a007d9df7769d3c63998dfeadda5ca17f1d15a

[bungeman-skia, 2015-06-18 22:23:51]

The CQ bit was checked by bungeman@google.com to run a CQ dry run

[commit-bot: I haz the power, 2015-06-18 22:24:00]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1180223005/1

[bungeman-skia, 2015-06-18 22:24:11]

bungeman@google.com changed reviewers:
+ mtklein@google.com

[commit-bot: I haz the power, 2015-06-18 22:29:14]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2015-06-18 22:29:16]

Dry run: This issue passed the CQ dry run.

[mtklein, 2015-06-19 12:08:50]

lgtm!

[mtklein, 2015-06-19 12:08:54]

The CQ bit was checked by mtklein@google.com

[commit-bot: I haz the power, 2015-06-19 12:09:05]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1180223005/1

[commit-bot: I haz the power, 2015-06-19 12:09:43]

Committed patchset #1 (id:1) as
https://skia.googlesource.com/skia/+/13a007d9df7769d3c63998dfeadda5ca17f1d15a