So what caused this? After a bit of searching, I found that Chromium created a .fonts.conf file in the home directory that didn't use smoothing. Actually, the fonts.conf file contains the font settings. The default file exists at /etc/fonts/fonts.conf. Now what I did is, deleted the file from my home directory and restarted the browsers. Now everything is ok.
You can either delete it from Nautilus or run in Terminal,
rm ~/.fonts.confYou can also copy your default font settings to the home directory by,
cp /etc/fonts/fonts.conf ~/.fonts.conf