Remove unused HostResolver::Observer.

net/base/host_resolver_impl.cc

Index: net/base/host_resolver_impl.cc
diff --git a/net/base/host_resolver_impl.cc b/net/base/host_resolver_impl.cc
index c4002e6a57cf33ebbabe84e39bbcaf43d0f3b25e..90db8b01d242dd3cd36d2151ba5e836693843c07 100644
--- a/net/base/host_resolver_impl.cc
+++ b/net/base/host_resolver_impl.cc
@@ -1262,22 +1262,6 @@ void HostResolverImpl::CancelRequest(RequestHandle req_handle) {
                   req->info());
 }
 
-void HostResolverImpl::AddObserver(HostResolver::Observer* observer) {
-  DCHECK(CalledOnValidThread());
-  observers_.push_back(observer);
-}
-
-void HostResolverImpl::RemoveObserver(HostResolver::Observer* observer) {
-  DCHECK(CalledOnValidThread());
-  ObserversList::iterator it =
-      std::find(observers_.begin(), observers_.end(), observer);
-
-  // Observer must exist.
-  DCHECK(it != observers_.end());
-
-  observers_.erase(it);
-}
-
 void HostResolverImpl::SetDefaultAddressFamily(AddressFamily address_family) {
   DCHECK(CalledOnValidThread());
   ipv6_probe_monitoring_ = false;
@@ -1443,14 +1427,6 @@ void HostResolverImpl::OnStartRequest(const BoundNetLog& source_net_log,
       NetLog::TYPE_HOST_RESOLVER_IMPL_REQUEST,
       make_scoped_refptr(new RequestInfoParameters(
           info, source_net_log.source())));
-
-  // Notify the observers of the start.
-  if (!observers_.empty()) {
-    for (ObserversList::iterator it = observers_.begin();
-         it != observers_.end(); ++it) {
-      (*it)->OnStartResolution(request_id, info);
-    }
-  }
 }
 
 void HostResolverImpl::OnFinishRequest(const BoundNetLog& source_net_log,
@@ -1461,14 +1437,6 @@ void HostResolverImpl::OnFinishRequest(const BoundNetLog& source_net_log,
                                        int os_error) {
   bool was_resolved = net_error == OK;
 
-  // Notify the observers of the completion.
-  if (!observers_.empty()) {
-    for (ObserversList::iterator it = observers_.begin();
-         it != observers_.end(); ++it) {
-      (*it)->OnFinishResolutionWithStatus(request_id, was_resolved, info);
-    }
-  }
-
   // Log some extra parameters on failure for synchronous requests.
   scoped_refptr<NetLog::EventParameters> params;
   if (!was_resolved) {
@@ -1484,15 +1452,6 @@ void HostResolverImpl::OnCancelRequest(const BoundNetLog& source_net_log,
                                        int request_id,
                                        const RequestInfo& info) {
   request_net_log.AddEvent(NetLog::TYPE_CANCELLED, NULL);
-
-  // Notify the observers of the cancellation.
-  if (!observers_.empty()) {
-    for (ObserversList::iterator it = observers_.begin();
-         it != observers_.end(); ++it) {
-      (*it)->OnCancelResolution(request_id, info);
-    }
-  }
-
   request_net_log.EndEvent(NetLog::TYPE_HOST_RESOLVER_IMPL_REQUEST, NULL);
   source_net_log.EndEvent(NetLog::TYPE_HOST_RESOLVER_IMPL, NULL);
 }