* Add @font-size-minerva-smallest and use it in place
of font-size: 0.8em across the site so that we get a round
number for our font sizes.
Bug: T229568
Change-Id: I4270225c07941b4c164d5e044f70d4b131dbc19d
* Remove ambiguity in imports - say the file extension
'less' for all instances of variables and mixins.
* Separate toast styles from drawer styles so they can be
imported separately
* associate header-action selector with its parent
(.overlay-header) not parent's parent (.overlay) so it can be imported
and rendered without the Overlay.
Change-Id: Ib7e19a440ba095d6424d35305fb41d643ca9764c
