Fix for crash in empty home page field. Ensure pref gets set back to NTP. BUG=11852.  Review URL: http://codereview.chromium.org/113363
Fix for crash in empty home page field. Ensure pref gets set back to NTP. BUG=11852. 
Review URL: http://codereview.chromium.org/113363

git-svn-id: dd90618784b6a4b323ea0c23a071cb1c9e6f2ac7@16274 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