add ignore for thumbs.db
add ignore for thumbs.db

git-svn-id: http://src.chromium.org/svn/trunk/src@20461 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

Former-commit-id: b081babe4ea1a899f3b853109be6d557662f988e
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