Reland "Add SkFontMgr implementation for Fuchsia"

This is a reland of 309f1deddf8ef0d5d2ce4f92c3be4c8ecd745b90

PS2 excludes the new file from Google3 build.

Original change's description:
> Add SkFontMgr implementation for Fuchsia
>
> The new SkFontMgr implementation will be used by Flutter and Chromium on
> Fuchsia.
>
> Change-Id: Ibd60a622282556e8557058e92fe865857f7024f9
> Reviewed-on: https://skia-review.googlesource.com/c/173800
> Reviewed-by: Ben Wagner <bungeman@google.com>
> Commit-Queue: Mike Klein <mtklein@google.com>

Change-Id: I1ea948b644dee4414b7a12a4b354f0a61a5e47ea
Reviewed-on: https://skia-review.googlesource.com/c/175431
Reviewed-by: Mike Klein <mtklein@google.com>
Commit-Queue: Mike Klein <mtklein@google.com>
4 files changed