[Win] Implement Authentication dialog in MiniBrowser

[Win] Implement Authentication dialog in MiniBrowser
https://bugs.webkit.org/show_bug.cgi?id=174662

Patch by Basuke Suzuki <Basuke.Suzuki@sony.com> on 2017-07-24
Reviewed by Alex Christensen.

* MiniBrowser/win/Common.cpp:
(CustomUserAgent):
(DisplayAuthDialog):
(AuthDialogProc):
* MiniBrowser/win/MiniBrowserLib.rc:
* MiniBrowser/win/MiniBrowserLibResource.h:
* MiniBrowser/win/ResourceLoadDelegate.cpp:
(ResourceLoadDelegate::didReceiveAuthenticationChallenge):

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@219830 268f45cc-cd09-0410-ab3c-d52691b4dbfc