Don't try to use explicit credentials with schemes that don't support it.

net/http/http_auth_handler.cc

-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "net/http/http_auth_handler.h"
 
 #include "base/logging.h"
 #include "net/base/net_errors.h"
 
 namespace net {
 
@@ skipping 71 matching lines @@
 }
 
 bool HttpAuthHandler::NeedsIdentity() {
   return true;
 }
 
 bool HttpAuthHandler::AllowsDefaultCredentials() {
   return false;
 }
 
+bool HttpAuthHandler::AllowsExplicitCredentials() {
+  return true;
+}
+
 void HttpAuthHandler::OnGenerateAuthTokenComplete(int rv) {
   CompletionCallback* callback = original_callback_;
   FinishGenerateAuthToken();
   if (callback)
     callback->Run(rv);
 }
 
 void HttpAuthHandler::FinishGenerateAuthToken() {
   // TOOD(cbentzel): Should this be done in OK case only?
   net_log_.EndEvent(EventTypeFromAuthTarget(target_), NULL);
   original_callback_ = NULL;
 }
 
 }  // namespace net