[V8] Notification.requestPermission(function() {alert();}) crashes

[V8] Notification.requestPermission(function() {alert();}) crashes
https://bugs.webkit.org/show_bug.cgi?id=94462

Reviewed by Adam Barth.

Source/WebCore:

Since Notification.requestPermission() is a static method,
we need to use getExecutionContext() instead of retrieving a context
from a DOM object.

Test: http/tests/notifications/notification-request-permission.html

* bindings/v8/custom/V8NotificationCustom.cpp:
(WebCore::V8Notification::requestPermissionCallback):

LayoutTests:

The added test checks if Notification.requestPermission() does not crash.

* http/tests/notifications/notification-request-permission-expected.txt: Added.
* http/tests/notifications/notification-request-permission.html: Added.

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@128959 268f45cc-cd09-0410-ab3c-d52691b4dbfc