Hi Yi Chen,
Yes it does. It comes with Midori - a lightweight web browser based on WebKit/GTK.
Midori is released under the GNU Lesser General Public License, version 2.1, which makes it suitable for inclusion in both proprietary and free, open-source programs.
For your information, It seems that Open Embedded project provides recipes for Firefox and Chromium (http://layers.openembedded.org/layerindex/branch/master/layer/meta-browser/ ), but these are not bundled with Wind River Linux and therefore not supported out of the box.