Make the output of notification testing in test shell match that of WebKit DumpRenderTree in the event of empty fields, rather than printing (null).
Make the output of notification testing in test shell match that of WebKit DumpRenderTree in the event of empty fields, rather than printing (null).

BUG=none
TEST=none

Review URL: http://codereview.chromium.org/1697006

git-svn-id: dd90618784b6a4b323ea0c23a071cb1c9e6f2ac7@45269 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