Correct const accessors in base/values.(h|cc)

chrome/browser/extensions/api/proxy/proxy_api_helpers.h

 // Copyright (c) 2012 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.
 
 // Definition of helper functions for the Chrome Extensions Proxy Settings API.
 
 #ifndef CHROME_BROWSER_EXTENSIONS_API_PROXY_PROXY_API_HELPERS_H_
 #define CHROME_BROWSER_EXTENSIONS_API_PROXY_PROXY_API_HELPERS_H_
 
 #include <string>
@@ skipping 82 matching lines @@
 // caller did not pass one.
 // Returns true if successful and sets |error| otherwise.
 bool GetProxyServer(const base::DictionaryValue* proxy_server,
                     net::ProxyServer::Scheme default_scheme,
                     net::ProxyServer* out,
                     std::string* error,
                     bool* bad_message);
 
 // Joins a list of URLs (stored as StringValues) in |list| with |joiner|
 // to |out|. Returns true if successful and sets |error| otherwise.
-bool JoinUrlList(base::ListValue* list,
+bool JoinUrlList(const base::ListValue* list,
                  const std::string& joiner,
                  std::string* out,
                  std::string* error,
                  bool* bad_message);
 
 
 // Helper functions for browser->extension pref transformation:
 
 // Creates and returns a ProxyRules dictionary as defined in the extension API
 // with the values of a ProxyConfigDictionary configured for fixed proxy
@@ skipping 14 matching lines @@
 
 // Tokenizes the |in| at delimiters |delims| and returns a new ListValue with
 // StringValues created from the tokens. Ownership is passed to the caller.
 base::ListValue* TokenizeToStringList(const std::string& in,
                                       const std::string& delims);
 
 }  // namespace proxy_api_helpers
 }  // namespace extensions
 
 #endif  // CHROME_BROWSER_EXTENSIONS_API_PROXY_PROXY_API_HELPERS_H_