Only allows extensions to create HTML notifications.
createHTMLNotification has been removed from the W3C Notifications spec. We do not want it to be exposed for web pages. However, since quite a few extensions are still using it, we would still keep it to be exposed for extensions.
BUG=
98061
TEST=existing tests
Committed:
http://src.chromium.org/viewvc/chrome?view=rev&revision=149054