wininet: Combine certificate errors in HTTP_OpenConnection

[Dan Kegel]

>> Test can't be easily added to wine because we don't have pages to test
>> certificate errors on.
>
>That should be addressed, no?  E.g. with a page hosted at winehq.org
>with a self-signed certificate?

Or look at how Chromium does its ssl unit tests, by launching a little
server written in python:
http://src.chromium.org/cgi-bin/gitweb.cgi?p=chromium.git;a=blob;f=net/socket/ssl_test_util.cc
http://src.chromium.org/cgi-bin/gitweb.cgi?p=chromium.git;a=blob;f=net/socket/ssl_client_socket_unittest.cc
- Dan