Revert "remove dead code around SK_SUPPORT_LEGACY_FONT_FLAGS"

This reverts commit 3b155a77c3704c3f3c5b741d60990e5ee959b261.

Reason for revert: breaks fuchsia (needs to roll newer flutter)

Original change's description:
> remove dead code around SK_SUPPORT_LEGACY_FONT_FLAGS
> 
> Bug: skia:
> Change-Id: I5a36e6827610c2a429e2f8b36adf432b95993c54
> Reviewed-on: https://skia-review.googlesource.com/c/171529
> Reviewed-by: Mike Reed <reed@google.com>
> Commit-Queue: Mike Reed <reed@google.com>

TBR=reed@google.com

Change-Id: I37bfab86e4a4243ddd94255aa0b126414bd9e835
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: skia:
Reviewed-on: https://skia-review.googlesource.com/c/171536
Reviewed-by: Mike Reed <reed@google.com>
Commit-Queue: Mike Reed <reed@google.com>
2 files changed