Check that BlockedContents::blocked_popup_container is not NULL before using it.
Check that BlockedContents::blocked_popup_container is not NULL before using it.

BUG=53176
TEST=None.
Review URL: http://codereview.chromium.org/3204003

git-svn-id: dd90618784b6a4b323ea0c23a071cb1c9e6f2ac7@57249 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser