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Eliminates the need to copy to/from C++ structs.

Change-Id: Ief0662701cad0b48ff68c2b04fed8ae1b858b6cb
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6437809
Reviewed-by: Carlos Knippschild <carlosk@chromium.org>
Reviewed-by: Michael Crouse <mcrouse@chromium.org>
Reviewed-by: Abigail Klein <abigailbklein@google.com>
Commit-Queue: Gary Klassen <gklassen@chromium.org>
Reviewed-by: Khushal Sagar <khushalsagar@chromium.org>
Reviewed-by: Ken Buchanan <kenrb@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1444460}