Revert "Add SkTypeface::getVariationDesignPosition."

Revert "Add SkTypeface::getVariationDesignPosition."

This reverts commit 87e7f820f74a990a59fb8f1d5c182584ce586ecf.

Reason for revert: Failed a test on Mac

Original change's description:
> Add SkTypeface::getVariationDesignPosition.
>
> Allow users to query a typeface's position in variation design space.
>
> Change-Id: I5d80c8ff658708a5d1aa386ec5b7396dcb621198
> Reviewed-on: https://skia-review.googlesource.com/7130
> Commit-Queue: Ben Wagner <bungeman@google.com>
> Reviewed-by: Mike Reed <reed@google.com>
>

TBR=bungeman@google.com,reed@google.com,reviews@skia.org,drott@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Change-Id: Ia65792083642dbe9333a62eb75d162931b57cffd
Reviewed-on: https://skia-review.googlesource.com/8670
Reviewed-by: Ben Wagner <bungeman@google.com>
Commit-Queue: Ben Wagner <bungeman@google.com>