A11Y: Fix post control and user-menu focus styles (PR #13118)

This fixes focus styles in the user menu and in post controls.

Before:

Screen Shot 2021-05-21 at 6 30 01 PM Screen Shot 2021-05-21 at 6 29 57 PM

After:

Screen Shot 2021-05-21 at 6 26 22 PM Screen Shot 2021-05-21 at 6 26 10 PM

GitHub

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