Cleanup: Use AUTH_SCHEME enum instead of a string.

net/http/http_auth_controller.h

 // 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.
 
 #ifndef NET_HTTP_HTTP_AUTH_CONTROLLER_H_
 #define NET_HTTP_HTTP_AUTH_CONTROLLER_H_
 #pragma once
 
 #include <set>
 #include <string>
@@ skipping 51 matching lines @@
   // Store the supplied credentials and prepare to restart the auth.
   virtual void ResetAuth(const string16& username,
                          const string16& password);
 
   virtual bool HaveAuthHandler() const;
 
   virtual bool HaveAuth() const;
 
   virtual scoped_refptr<AuthChallengeInfo> auth_info();
 
-  virtual bool IsAuthSchemeDisabled(const std::string& scheme) const;
-  virtual void DisableAuthScheme(const std::string& scheme);
+  virtual bool IsAuthSchemeDisabled(HttpAuth::Scheme scheme) const;
+  virtual void DisableAuthScheme(HttpAuth::Scheme scheme);
 
  private:
   // So that we can mock this object.
   friend class base::RefCounted<HttpAuthController>;
 
   virtual ~HttpAuthController();
 
   // Searches the auth cache for an entry that encompasses the request's path.
   // If such an entry is found, updates |identity_| and |handler_| with the
   // cache entry's data and returns true.
@@ skipping 55 matching lines @@
   // True if default credentials have already been tried for this transaction
   // in response to an HTTP authentication challenge.
   bool default_credentials_used_;
 
   // These two are owned by the HttpNetworkSession/IOThread, which own the
   // objects which reference |this|.  Therefore, these raw pointers are valid
   // for the lifetime of this object.
   HttpAuthCache* const http_auth_cache_;
   HttpAuthHandlerFactory* const http_auth_handler_factory_;
 
-  std::set<std::string> disabled_schemes_;
+  std::set<HttpAuth::Scheme> disabled_schemes_;
 
   CompletionCallbackImpl<HttpAuthController> io_callback_;
   CompletionCallback* user_callback_;
 };
 
 }  // namespace net
 
 #endif  // NET_HTTP_HTTP_AUTH_CONTROLLER_H_