Allow ProxyConfigService to report "no configuration set"

net/proxy/polling_proxy_config_service.cc

Index: net/proxy/polling_proxy_config_service.cc
diff --git a/net/proxy/polling_proxy_config_service.cc b/net/proxy/polling_proxy_config_service.cc
index 7526c192c0375db0129144e388269ca47fe89d7e..28e3a65f66690134dddee600cb218cfc6952d4af 100644
--- a/net/proxy/polling_proxy_config_service.cc
+++ b/net/proxy/polling_proxy_config_service.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// 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.
 
@@ -121,7 +121,9 @@ class PollingProxyConfigService::Core
       // If the configuration has changed, notify the observers.
       has_config_ = true;
       last_config_ = config;
-      FOR_EACH_OBSERVER(Observer, observers_, OnProxyConfigChanged(config));
+      FOR_EACH_OBSERVER(Observer, observers_,
+                        OnProxyConfigChanged(config,
+                                             ProxyConfigService::CONFIG_VALID));
     }
 
     if (poll_task_queued_)
@@ -162,8 +164,9 @@ void PollingProxyConfigService::RemoveObserver(Observer* observer) {
   core_->RemoveObserver(observer);
 }
 
-bool PollingProxyConfigService::GetLatestProxyConfig(ProxyConfig* config) {
-  return core_->GetLatestProxyConfig(config);
+ProxyConfigService::ConfigAvailability
+    PollingProxyConfigService::GetLatestProxyConfig(ProxyConfig* config) {
+  return core_->GetLatestProxyConfig(config) ? CONFIG_VALID : CONFIG_PENDING;
 }
 
 void PollingProxyConfigService::OnLazyPoll() {