update dnd registry enum to work properly with bitmask
update dnd registry enum to work properly with bitmask

TBR=erg

Review URL: http://codereview.chromium.org/150033

git-svn-id: http://src.chromium.org/svn/trunk/src@19503 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

Former-commit-id: a366e11a51e7c2a4520723de200202261b8b32f1
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