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For unique local font matching, on Windows 10, we do not need to scan
fonts and build a lookup structure but instead we can perform lookups
directly against IDWriteFontSet using GetMatchingFonts() API. This API
is only available where IDWriteFactory3 is available, which means on
Windows 10.

Add a method to DWriteFontProxy to perform a single font lookup using
this API. Also add a method to dermine which mode should be used on the
current machine: single lookups or retrieving the shared-memory lookup
table that we built for Windows 7 and 8.

See the design document [1] for more details.

[1] https://docs.google.com/document/d/1yCZwVIF39S8WOgCUraT5OuUUaLSqWrxoG3mqdtnHnhs/edit#heading=h.s74lqnekmr53

Bug: 951978
Change-Id: I833139238a47ba9e72f643656a75c2e78c069343
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1565310
Commit-Queue: Dominik Röttsches <drott@chromium.org>
Reviewed-by: Ben Wagner <bungeman@google.com>
Reviewed-by: Avi Drissman <avi@chromium.org>
Reviewed-by: Robert Sesek <rsesek@chromium.org>
Cr-Commit-Position: refs/heads/master@{#650459}