select: increasing font size of select increases font size of options, reseting it back to base value messes up positioning

[fxck]

https://stackblitz.com/edit/angular-material2-issue-d1e88y?file=styles.scss

select third option, close, open select again

a) it didn't increase font size of option pre form-field
b) positioning was working correctly, despite different font size, pre form-field

cc @crisbeto

[fxck]

In case you are wondering why would I want different item size for options and select

there's no reason why would I want the options to be as big as the active option, quite the opposite, it would look pretty bad, and be pretty bad UX, since barely three options would fit into one "screen".

This is what "broke" it d914cc4#diff-102eaa94de98ed2cabd87565ba514125R89 @mmalerba

#7627 and #7638 are both related to the same component, it's nearly impossible to do something like this with material, especially since the mat-form-field stuff, I completely understand components like these are not part of the material spec, but it would be nice if slight style modifications would be even possible, especially when it's just about styling most of the time, not the internal apis.

[mmalerba]

I'll take a look and see if we can do the positioning based on the option size instead of the trigger size, just in case people override it like you're doing.