To enable font scaling that can be adjusted via Android Settings-app:
Accessibility -> Display size and text -> Font size
Adds options.topBar.title.allowFontScaling
Adds and updated unit tests
When allowFontScaling is enabled, sets top bar title to use SP units. When font scaling is 1.0, it should be the same size as when using DIP
Here it's set to false by default, because it can conflict with other top bar options like subtitle, height, fontSize etc. that existing users may have
I'm thinking about making similar changes to iOS, but I wanted feedback on this one first. iOS has some issues especially when "Larger accessibility sizes"-setting is enabled
Accessibility -> Display size and text -> Font size
Allowing font scaling in top bar title seems to be convention in "standard" Android apps:
Settings that can change font scaling in users' device