We encountered an issue where PolyGerrit was not respecting browser
font preferences. Browser font preferences include both a default font
size and a minimum font size.
In the event that a font declared in px is smaller than the minimum font
size, the size is increased to equal the minimum font size. However,
if the font is declared in px and greater than the minimum, the
preferred font size is not taken into account.
Browsers' default font size is 16px [1], So instead of declaring the
base font in px (previously 13px), this change makes it a percentage
of the default font size. If the user has changed their default, this
is taken into account.
From this point, all other fonts will be declared in rems, which makes
it easier to base the new size off of the base font size of the <html>
tag, rather than ems which bases it on the container[2]. This allows us
to declare font sizes in a way more similar to pixels, yet relative.
A follow-up change will change all font size declaration to use rem from
em for consistency.
[1] https://stackoverflow.com/questions/29511983/is-the-default-font-size-of-every-browser-16px-why
[2] https://webdesign.tutsplus.com/tutorials/comprehensive-guide-when-to-use-em-vs-rem--cms-23984
Bug: Issue 8157
Change-Id: I04ec2c861b2fb288ec7556dfb655d7feea9c9157
d450a9eb57