Update DOMUI pref style
Update DOMUI pref style

This makes a few small changes to bring things more in line with the latest mocks:
- Larger font size for page and section titles.
- Removes the trailing divider line after the last section.
- Tweaks the inter-section spacing.

BUG=59237,59264
TEST=DOMUI prefs should look more like mocks.

Review URL: http://codereview.chromium.org/4826002

git-svn-id: http://src.chromium.org/svn/trunk/src@65870 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

Former-commit-id: cfbe518231a678e46283508837009145989b93ec
meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser