Revert "Revert "nav bar font styles are special, do not inherit (#12578)"" (#12679)
Revert "Revert "nav bar font styles are special, do not inherit (#12578)"" (#12679)

* Revert "roll engine (#12660)"

This reverts commit 048bc5e0f6fe96d07bc7777792e31f96f855d5da.

* Revert "FittedBox RTL (#12662)"

This reverts commit 05a22fe0ab2e74635db6628a7fc125e1a1f20203.

* Revert "Revert "nav bar font styles are special, do not inherit (#12578)" (#12661)"

This reverts commit 662b66848562df022dcf95134b61e9958a5a74f4.

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