Fail rather than crash if username+password are unspecified for NTLM on Linux+OSX.

net/http/http_auth_handler_ntlm.cc

 // Copyright (c) 2010 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_ntlm.h"
 
 #if !defined(NTLM_SSPI)
 #include "base/base64.h"
 #endif
 #include "base/logging.h"
@@ skipping 10 matching lines @@
     const HttpRequestInfo* request,
     CompletionCallback* callback,
     std::string* auth_token) {
 #if defined(NTLM_SSPI)
   return auth_sspi_.GenerateAuthToken(
       username,
       password,
       CreateSPN(origin_),
       auth_token);
 #else  // !defined(NTLM_SSPI)
+  // TODO(cbentzel): Shouldn't be hitting this case.
+  if (!username || !password) {
+    LOG(ERROR) << "Username and password are expected to be non-NULL.";
+    return ERR_MISSING_AUTH_CREDENTIALS;
+  }
   // TODO(wtc): See if we can use char* instead of void* for in_buf and
   // out_buf.  This change will need to propagate to GetNextToken,
   // GenerateType1Msg, and GenerateType3Msg, and perhaps further.
   const void* in_buf;
   void* out_buf;
   uint32 in_buf_len, out_buf_len;
   std::string decoded_auth_data;
 
   // |username| may be in the form "DOMAIN\user".  Parse it into the two
   // components.
@@ skipping 73 matching lines @@
 // static
 std::wstring HttpAuthHandlerNTLM::CreateSPN(const GURL& origin) {
   // The service principal name of the destination server.  See
   // http://msdn.microsoft.com/en-us/library/ms677949%28VS.85%29.aspx
   std::wstring target(L"HTTP/");
   target.append(ASCIIToWide(GetHostAndPort(origin)));
   return target;
 }
 
 }  // namespace net