Use SSPI for NTLM authentication on Windows.

[Second attempt of r25461]

Use SSPI for NTLM authentication on Windows.

Add an explicit embedded_identity_used_ boolean member to
make sure we use the username/password in the URL only once
for the transaction.  This allows us to reset
auth_identity_[target].source to HttpAuth::IDENT_SRC_NONE
after auth failed.

Initial patch by Arindam.

Original review URL: http://codereview.chromium.org/159656

R=arindam,eroman
BUG=19, 18009, 20560
TEST=1. Open a webpage that requests NTLM authentication
on Windows.  2. New unit test for wrong auth identity in
URL.

Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=25564

[eroman, 2009-09-05 00:32:27]

LGTM.

Thanks for adding the new unittest!

http://codereview.chromium.org/193022/diff/6011/7009
File net/http/http_network_transaction_unittest.cc (right):

http://codereview.chromium.org/193022/diff/6011/7009#newcode2234
Line 2234: request.load_flags = 0;
can you use LOAD_NORMAL instead?

Hmm, seems we do the " = 0" business elsewhere.