[Qt][WK2] Move code common to both ProxyAuthentication and Authentication context...

[Qt][WK2] Move code common to both ProxyAuthentication and Authentication context objects into a base class
https://bugs.webkit.org/show_bug.cgi?id=80627

Patch by Dinu Jacob <dinu.jacob@nokia.com> on 2012-03-14
Reviewed by Kenneth Rohde Christiansen.

No impact to QML API.

* UIProcess/qt/QtDialogRunner.cpp:
(BaseAuthenticationContextObject):
(BaseAuthenticationContextObject::BaseAuthenticationContextObject):
(HttpAuthenticationDialogContextObject):
(HttpAuthenticationDialogContextObject::HttpAuthenticationDialogContextObject):
(HttpAuthenticationDialogContextObject::realm):
(ProxyAuthenticationDialogContextObject):
(ProxyAuthenticationDialogContextObject::ProxyAuthenticationDialogContextObject):
(QtDialogRunner::initForAuthentication):

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@110781 268f45cc-cd09-0410-ab3c-d52691b4dbfc