Preliminary work on resuming downloads whose connections have expired.

net/url_request/url_request.cc

 // 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.
 
 #include "net/url_request/url_request.h"
 
 #include "base/compiler_specific.h"
 #include "base/message_loop.h"
 #include "base/singleton.h"
 #include "base/stats_counters.h"
@@ skipping 164 matching lines @@
 void URLRequest::SetExtraRequestHeaderById(int id, const string& value,
                                            bool overwrite) {
   DCHECK(!is_pending_);
   NOTREACHED() << "implement me!";
 }
 
 void URLRequest::SetExtraRequestHeaderByName(const string& name,
                                              const string& value,
                                              bool overwrite) {
   DCHECK(!is_pending_);
-  NOTREACHED() << "implement me!";
+  if (!overwrite || !extra_request_headers_.HasHeader(name))
+    extra_request_headers_.SetHeader(name, value);
 }
 
 void URLRequest::SetExtraRequestHeaders(
     const net::HttpRequestHeaders& headers) {
   DCHECK(!is_pending_);
-  extra_request_headers_ = headers;
+  extra_request_headers_.MergeFrom(headers);
 
   // NOTE: This method will likely become non-trivial once the other setters
   // for request headers are implemented.
 }
 
 net::LoadState URLRequest::GetLoadState() const {
   return job_ ? job_->GetLoadState() : net::LOAD_STATE_IDLE;
 }
 
 uint64 URLRequest::GetUploadProgress() const {
@@ skipping 377 matching lines @@
 URLRequest::UserData* URLRequest::GetUserData(const void* key) const {
   UserDataMap::const_iterator found = user_data_.find(key);
   if (found != user_data_.end())
     return found->second.get();
   return NULL;
 }
 
 void URLRequest::SetUserData(const void* key, UserData* data) {
   user_data_[key] = linked_ptr<UserData>(data);
 }