Check notification permissions in the show() method
https://bugs.webkit.org/show_bug.cgi?id=108009

Reviewed by Adam Barth.

Source/WebCore:

Tests: fast/notifications/notifications-constructor-with-permission.html
       fast/notifications/notifications-constructor-without-permission.html

* Modules/notifications/Notification.cpp:
(WebCore::Notification::show):
(WebCore::Notification::taskTimerFired):

LayoutTests:

* fast/notifications/notifications-constructor-with-permission-expected.txt: Added.
* fast/notifications/notifications-constructor-with-permission.html: Added.
* fast/notifications/notifications-constructor-without-permission-expected.txt: Added.
* fast/notifications/notifications-constructor-without-permission.html: Added.


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@140927 268f45cc-cd09-0410-ab3c-d52691b4dbfc