Note this actually changes the "subtle" color to be darker. As far
as I understand this is an intentional decision. The old color token
from OOUI is deprecated and intentionally made darker in Codex.
See Ie667c35 and most notably T313502.
Change-Id: I37ad25aa6821d61fe3321e1390d1ccf987075250
Same as in I7e82e03. The extra "shield" element was added in
2013 (!), see Ib244ff6. Back then we couldn't use the CSS property.
But nowadays we can.
Bug: T360034
Bug: T367030
Change-Id: Ib41e062491e65eabc8a52facefe283ba04ce16ff