Remove `inline-block` from message boxes

Remove `inline-block` from message boxes

Removing `inline-block` from message boxes as they're outlined as
block level elements in UI standardization work.
Back in Ibb9371eec in 2013 those were used in various contexts and
tried to resolve the back then stated need of intrinsic width by
`inline-block`. That doesn't seem to be appropriate for the general
use case any more.
If used in other contexts or on inline elements, product owners and
implementors need to act on specifically adapting them.

Bug: T233359
Change-Id: I530fda47b3d7b99f782b421abbde8957026570cd