Remove the unused source_net_log parameter from ResolveHelper.

net/base/host_resolver_impl.cc

 // Copyright (c) 2011 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/base/host_resolver_impl.h"
 
 #if defined(OS_WIN)
 #include <Winsock2.h>
 #elif defined(OS_POSIX)
 #include <netdb.h>
@@ skipping 1141 matching lines @@
   BoundNetLog request_net_log = BoundNetLog::Make(net_log_,
       NetLog::SOURCE_HOST_RESOLVER_IMPL_REQUEST);
 
   // Update the net log and notify registered observers.
   OnStartRequest(source_net_log, request_net_log, request_id, info);
 
   // Build a key that identifies the request in the cache and in the
   // outstanding jobs map.
   Key key = GetEffectiveKeyForRequest(info);
 
-  int rv = ResolveHelper(request_id, key, info, addresses,
-                         source_net_log, request_net_log);
+  int rv = ResolveHelper(request_id, key, info, addresses, request_net_log);
   if (rv != ERR_DNS_CACHE_MISS) {
     OnFinishRequest(source_net_log, request_net_log, request_id, info,
                     rv,
                     0  /* os_error (unknown since from cache) */);
     return rv;
   }
 
    // Create a handle for this request, and pass it back to the user if they
   // asked for it (out_req != NULL).
   Request* req = new Request(source_net_log, request_net_log, request_id, info,
@@ skipping 20 matching lines @@
   }
 
   // Completion happens during OnJobComplete(Job*).
   return ERR_IO_PENDING;
 }
 
 int HostResolverImpl::ResolveHelper(int request_id,
                                     const Key& key,
                                     const RequestInfo& info,
                                     AddressList* addresses,
-                                    const BoundNetLog& request_net_log,
-                                    const BoundNetLog& source_net_log) {
+                                    const BoundNetLog& request_net_log) {
   // The result of |getaddrinfo| for empty hosts is inconsistent across systems.
   // On Windows it gives the default interface's address, whereas on Linux it
   // gives an error. We will make it fail on all platforms for consistency.
   if (info.hostname().empty() || info.hostname().size() > kMaxHostLength)
     return ERR_NAME_NOT_RESOLVED;
 
   int net_error = ERR_UNEXPECTED;
   if (ResolveAsIP(key, info, &net_error, addresses))
     return net_error;
   net_error = ERR_DNS_CACHE_MISS;
@@ skipping 14 matching lines @@
   BoundNetLog request_net_log = BoundNetLog::Make(net_log_,
       NetLog::SOURCE_HOST_RESOLVER_IMPL_REQUEST);
 
   // Update the net log and notify registered observers.
   OnStartRequest(source_net_log, request_net_log, request_id, info);
 
   // Build a key that identifies the request in the cache and in the
   // outstanding jobs map.
   Key key = GetEffectiveKeyForRequest(info);
 
-  int rv = ResolveHelper(request_id, key, info, addresses, request_net_log,
-                         source_net_log);
+  int rv = ResolveHelper(request_id, key, info, addresses, request_net_log);
   OnFinishRequest(source_net_log, request_net_log, request_id, info,
                   rv,
                   0  /* os_error (unknown since from cache) */);
   return rv;
 }
 
 // See OnJobComplete(Job*) for why it is important not to clean out
 // cancelled requests from Job::requests_.
 void HostResolverImpl::CancelRequest(RequestHandle req_handle) {
   DCHECK(CalledOnValidThread());
@@ skipping 88 matching lines @@
   DCHECK(addresses);
   DCHECK(net_error);
   if (!info.allow_cached_response() || !cache_.get())
     return false;
 
   const HostCache::Entry* cache_entry = cache_->Lookup(
       key, base::TimeTicks::Now());
   if (!cache_entry)
     return false;
 
   request_net_log.AddEvent(NetLog::TYPE_HOST_RESOLVER_IMPL_CACHE_HIT, NULL);

[wtc, 2011/10/11 21:24:18]

Note that in the original code, Resolve passes source_net_log
and request_net_log to ResolveHelper in the wrong order.

The consequence of this bug is that the
NetLog::TYPE_HOST_RESOLVER_IMPL_CACHE_HIT event here is
added to the wrong net log (actually source_net_log)
when Resolve is called.

[wtc, 2011/10/11 21:30:09]

I forgot to mention that the original code before
http://codereview.chromium.org/7492059/ also added this
event to request_net_log.  See
http://codereview.chromium.org/7492059/diff/21034/net/base/host_resolver_impl...

This is why I concluded request_net_log is the intended net
log for ServeFromCache and ResolveHelper.

   *net_error = cache_entry->error;
   if (*net_error == OK)
     *addresses = CreateAddressListUsingPort(cache_entry->addrlist, info.port());
   return true;
 }
 
 void HostResolverImpl::AddOutstandingJob(Job* job) {
   scoped_refptr<Job>& found_job = jobs_[job->key()];
   DCHECK(!found_job);
   found_job = job;
@@ skipping 298 matching lines @@
   // resolv.conf changes so we don't need to do anything to clear that cache.
   if (cache_.get())
     cache_->clear();
   // Existing jobs will have been sent to the original server so they need to
   // be aborted. TODO(Craig): Should these jobs be restarted?
   AbortAllInProgressJobs();
   // |this| may be deleted inside AbortAllInProgressJobs().
 }
 
 }  // namespace net