Don't paint the throbber animation while dragging.
Don't paint the throbber animation while dragging.

Windows doesn't paint the throbber either, so we match.  We can
probably add it back in if we want, but it might not be worth
the effort.

BUG=20750

Review URL: http://codereview.chromium.org/183039


git-svn-id: http://src.chromium.org/svn/trunk/src@25128 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

Former-commit-id: b42d69fb8df590548e6da769f96cc15cd0de7c57
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