Incorrect tabbar icon height selector during merge.

You brought the i.icon height override in at the wrong level, so it isn't being applied.
You have to understand that this selector is very strict, so it could provide more problem for devs, if they will want to change this size, because in this case they will need to write same strict selector each time, for example:
```
.tabbar.tabbar-labels a.tab-link i.icon.my-icon {
  height:25px;
}
```
It also will not allow me/them/you to reuse the same icons in few places, so they will have additional tabbar icon style for each icon, right? :)

And, by the way this selector doesn't cover tab bar icons usage. We may have tabbar without tabbar-labels, and we may have `<a>` without "tab-link" class, it could be just "link". 

And as you may agree, that there is no bulletproof solution here. Only two options:
* we do such strict selector and make developers life a bit complicated with custom icons in tab bar
* or we leave it like it is with not strict selector, and dev could easily add one-two custom rules for tab bar icons. This option looks more painless for me

So maybe we may keep it like it is? :)