Mark URLRequest::GetResponseCode() as const

net/url_request/url_request.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.
 
 #ifndef NET_URL_REQUEST_URL_REQUEST_H_
 #define NET_URL_REQUEST_URL_REQUEST_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 510 matching lines @@
   // OnResponseStarted method has been called.
   void GetMimeType(std::string* mime_type);
 
   // Get the charset (character encoding).  This method may only be called once
   // the delegate's OnResponseStarted method has been called.
   void GetCharset(std::string* charset);
 
   // Returns the HTTP response code (e.g., 200, 404, and so on).  This method
   // may only be called once the delegate's OnResponseStarted method has been
   // called.  For non-HTTP requests, this method returns -1.
-  int GetResponseCode();
+  int GetResponseCode() const;
 
   // Get the HTTP response info in its entirety.
   const HttpResponseInfo& response_info() const { return response_info_; }
 
   // Access the LOAD_* flags modifying this request (see load_flags.h).
   int load_flags() const { return load_flags_; }
   void set_load_flags(int flags) { load_flags_ = flags; }
 
   // Returns true if the request is "pending" (i.e., if Start() has been called,
   // and the response has not yet been called).
@@ skipping 317 matching lines @@
   LoadTimingInfo load_timing_info_;
 
   scoped_ptr<const base::debug::StackTrace> stack_trace_;
 
   DISALLOW_COPY_AND_ASSIGN(URLRequest);
 };
 
 }  // namespace net
 
 #endif  // NET_URL_REQUEST_URL_REQUEST_H_