Don't crash when dragging bookmarks from one bookmark bar to another (as with multiple chrome windows).
Don't crash when dragging bookmarks from one bookmark bar to another (as with multiple chrome windows).

BUG=none
TEST=drag a bookmark icon from one a bookmark bar to a bar in another window without crashing.

Review URL: http://codereview.chromium.org/119114

git-svn-id: http://src.chromium.org/svn/trunk/src@17659 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

Former-commit-id: 05b5b7652a16064cc0d6717436c8894c2766bdcb
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