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

net/http/http_cache_transaction.h

Index: net/http/http_cache_transaction.h
diff --git a/net/http/http_cache_transaction.h b/net/http/http_cache_transaction.h
index 665f92f3b54ef340c6d6c505ef95bb3f8bff01c1..99b8e078b882f03e043a0c58cc2faa9985666d22 100644
--- a/net/http/http_cache_transaction.h
+++ b/net/http/http_cache_transaction.h
@@ -103,8 +103,7 @@ class HttpCache::Transaction : public HttpTransaction {
   virtual int RestartIgnoringLastError(OldCompletionCallback* callback);
   virtual int RestartWithCertificate(X509Certificate* client_cert,
                                      OldCompletionCallback* callback);
-  virtual int RestartWithAuth(const string16& username,
-                              const string16& password,
+  virtual int RestartWithAuth(const AuthCredentials& credentials,
                               OldCompletionCallback* callback);
   virtual bool IsReadyToRestartForAuth();
   virtual int Read(IOBuffer* buf, int buf_len, OldCompletionCallback* callback);
@@ -258,8 +257,7 @@ class HttpCache::Transaction : public HttpTransaction {
 
   // Called to restart a network transaction with authentication credentials.
   // Returns network error code.
-  int RestartNetworkRequestWithAuth(const string16& username,
-                                    const string16& password);
+  int RestartNetworkRequestWithAuth(const AuthCredentials& credentials);
 
   // Called to determine if we need to validate the cache entry before using it.
   bool RequiresValidation();