new cursor resource for xterm (ibeam)

TBR=sky@chromium.org
BUG=none
TEST=none

Review URL: https://chromiumcodereview.appspot.com/10392193

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@138227 0039d316-1c4b-4281-b951-d872f2087c98