Need to multiply pixel by basefontsize for proper pixel fallback value.

The pixel fallback values are a little bit off. If basefontsize is set to 16px, the pixel fallback values need to be multiplied by the basefontsize, so you should see:

body {
  font-size: 25.6px;
  font-size: 1.6rem;
}

I set my default basefontsize to 10px, so in my setup, I should see:

body {
  font-size: 16px;
  font-size: 1.6rem;
}

Currently, in master, I'm seeing:

body {
  font-size: 1.6px;
  font-size: 1.6rem;
}

On a side note, what are the chances of formatting the code so it's 2 spaces per tab...