Create the document font using normal FontBuilder calls.

Create the document font using normal FontBuilder calls.

FontBuilder::createFontForDocument presumably exists because FontBuilder
used to be dependent on CSSValues and/or because it made an unnecessary
amount of comparisons between FontDescriptions. This is no longer the
case, so we don't need special code for the document font anymore.

This also removes the need the arbitrary-FontDescription versions of some
of the FontBuilder functions, and these have how been folded into their
respective main functions. (setFamilyDescription, setSize,
updateComputedSize).

Also, rename Document::setupFontBuilder to Document::createFont.

R=dglazkov@chromium.org

[dglazkov, 2014-11-18 15:47:27]

lgtm