Use AuthCredentials throughout the network stack instead of username/password.

net/http/http_auth_handler_ntlm_portable.cc

Index: net/http/http_auth_handler_ntlm_portable.cc
diff --git a/net/http/http_auth_handler_ntlm_portable.cc b/net/http/http_auth_handler_ntlm_portable.cc
index 92b3e5bc3296d3eb76ebefcf9d2d93c945a796c7..d5febb68d30d98f9475d1bfbf428069a88393d51 100644
--- a/net/http/http_auth_handler_ntlm_portable.cc
+++ b/net/http/http_auth_handler_ntlm_portable.cc
@@ -19,6 +19,7 @@
 #include "base/utf_string_conversions.h"
 #include "net/base/net_errors.h"
 #include "net/base/net_util.h"
+#include "net/base/zap.h"
 #include "net/http/des.h"
 #include "net/http/md4.h"
 
@@ -238,20 +239,6 @@ static uint32 ReadUint32(const uint8*& buf) {
 
 //-----------------------------------------------------------------------------
 
-static void ZapBuf(void* buf, size_t buf_len) {
-  memset(buf, 0, buf_len);
-}
-
-// TODO(wtc): Can we implement ZapString as
-// s.replace(0, s.size(), s.size(), '\0)?
-static void ZapString(std::string* s) {
-  ZapBuf(&(*s)[0], s->length());
-}
-
-static void ZapString(string16* s) {
-  ZapBuf(&(*s)[0], s->length() * 2);
-}
-
 // LM_Hash computes the LM hash of the given password.
 //
 // param password
@@ -661,9 +648,7 @@ int HttpAuthHandlerNTLM::InitializeBeforeFirstChallenge() {
 }
 
 HttpAuthHandlerNTLM::~HttpAuthHandlerNTLM() {
-  // Wipe our copy of the password from memory, to reduce the chance of being
-  // written to the paging file on disk.
-  ZapString(&password_);
+  credentials_.Zap();
 }
 
 // static
@@ -703,7 +688,9 @@ int HttpAuthHandlerNTLM::GetNextToken(const void* in_token,
       return ERR_UNEXPECTED;
     uint8 rand_buf[8];
     generate_random_proc_(rand_buf, 8);
-    rv = GenerateType3Msg(domain_, username_, password_, hostname, rand_buf,
+    rv = GenerateType3Msg(domain_,
+                          credentials_.username(), credentials_.password(),
+                          hostname, rand_buf,
                           in_token, in_token_len, out_token, out_token_len);
   } else {
     rv = GenerateType1Msg(out_token, out_token_len);