Tell PDF on Mac when a font is a variation font.

PDF needs to know when a font is a variation font so that it knows
it cannot just embed the typeface.

BUG=chromium:697916

Change-Id: I85091e444a235545f0f63fe131729c107bb664a0
Reviewed-on: https://skia-review.googlesource.com/9158
Reviewed-by: Hal Canary <halcanary@google.com>
Commit-Queue: Ben Wagner <bungeman@google.com>
1 file changed