[chromium] add missing plumbing for Notification.requestPermission
https://bugs.webkit.org/show_bug.cgi?id=108012

Reviewed by Adam Barth.

Source/WebKit/chromium:

* src/NotificationPresenterImpl.cpp:
(WebKit):
(WebKit::VoidCallbackClient::VoidCallbackClient):
(NotificationPermissionCallbackClient):
(WebKit::NotificationPermissionCallbackClient::NotificationPermissionCallbackClient):
(WebKit::NotificationPermissionCallbackClient::permissionRequestComplete):
(WebKit::NotificationPermissionCallbackClient::~NotificationPermissionCallbackClient):
(WebKit::NotificationPresenterImpl::requestPermission):
* src/NotificationPresenterImpl.h:
(NotificationPresenterImpl):

LayoutTests:

* fast/notifications/notifications-constructor-request-permission-expected.txt: Added.
* fast/notifications/notifications-constructor-request-permission.html: Added.


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@140928 268f45cc-cd09-0410-ab3c-d52691b4dbfc