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..aee5abfe1aeb8226d17ce6cf483b83aa8227fbae 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.
 
@@ -24,7 +24,7 @@ class PollingProxyConfigService::Core
       : get_config_func_(get_config_func),
         poll_interval_(poll_interval),
         have_initialized_origin_loop_(false),
-        has_config_(false),
+        config_availability_(ProxyConfigService::CONFIG_PENDING),
         poll_task_outstanding_(false),
         poll_task_queued_(false) {
   }
@@ -36,7 +36,8 @@ class PollingProxyConfigService::Core
     origin_loop_proxy_ = NULL;
   }
 
-  bool GetLatestProxyConfig(ProxyConfig* config) {
+  ProxyConfigService::ConfigAvailability GetLatestProxyConfig(
+      ProxyConfig* config) {
     LazyInitializeOriginLoop();
     DCHECK(origin_loop_proxy_->BelongsToCurrentThread());
 
@@ -44,11 +45,10 @@ class PollingProxyConfigService::Core
 
     // If we have already retrieved the proxy settings (on worker thread)
     // then return what we last saw.
-    if (has_config_) {
+    if (config_availability_ == ProxyConfigService::CONFIG_VALID)
       *config = last_config_;
-      return true;
-    }
-    return false;
+
+    return config_availability_;
   }
 
   void AddObserver(Observer* observer) {
@@ -97,18 +97,21 @@ class PollingProxyConfigService::Core
  private:
   void PollOnWorkerThread(GetConfigFunction func) {
     ProxyConfig config;
-    func(&config);
+    ProxyConfigService::ConfigAvailability available = func(&config);
 
     base::AutoLock l(lock_);
     if (origin_loop_proxy_) {
       origin_loop_proxy_->PostTask(
           FROM_HERE,
-          NewRunnableMethod(this, &Core::GetConfigCompleted, config));
+          NewRunnableMethod(this, &Core::GetConfigCompleted,
+                            config, available));
     }
   }
 
   // Called after the worker thread has finished retrieving a configuration.
-  void GetConfigCompleted(const ProxyConfig& config) {
+  void GetConfigCompleted(
+      const ProxyConfig& config,
+      ProxyConfigService::ConfigAvailability available) {
     DCHECK(poll_task_outstanding_);
     poll_task_outstanding_ = false;
 
@@ -117,11 +120,15 @@ class PollingProxyConfigService::Core
 
     DCHECK(origin_loop_proxy_->BelongsToCurrentThread());
 
-    if (!has_config_ || !last_config_.Equals(config)) {
+    if (config_availability_ != available ||
+        (available == ProxyConfigService::CONFIG_VALID &&
+            !last_config_.Equals(config))) {
       // If the configuration has changed, notify the observers.
-      has_config_ = true;
+      config_availability_ = available;
       last_config_ = config;
-      FOR_EACH_OBSERVER(Observer, observers_, OnProxyConfigChanged(config));
+      FOR_EACH_OBSERVER(Observer, observers_,
+                        OnProxyConfigChanged(last_config_,
+                                             config_availability_));
     }
 
     if (poll_task_queued_)
@@ -149,7 +156,7 @@ class PollingProxyConfigService::Core
   scoped_refptr<base::MessageLoopProxy> origin_loop_proxy_;
 
   bool have_initialized_origin_loop_;
-  bool has_config_;
+  ProxyConfigService::ConfigAvailability config_availability_;
   bool poll_task_outstanding_;
   bool poll_task_queued_;
 };
@@ -162,7 +169,8 @@ void PollingProxyConfigService::RemoveObserver(Observer* observer) {
   core_->RemoveObserver(observer);
 }
 
-bool PollingProxyConfigService::GetLatestProxyConfig(ProxyConfig* config) {
+ProxyConfigService::ConfigAvailability
+    PollingProxyConfigService::GetLatestProxyConfig(ProxyConfig* config) {
   return core_->GetLatestProxyConfig(config);
 }