Fixed minor atomicity issue in PrefProxyConfigService::GetLatestProxyConfig.

chrome/browser/net/pref_proxy_config_service.cc

Index: chrome/browser/net/pref_proxy_config_service.cc
diff --git a/chrome/browser/net/pref_proxy_config_service.cc b/chrome/browser/net/pref_proxy_config_service.cc
index 5cd62136945832d5832a5929d6f8a5615d6eb6fb..5a9f006a3d824c10c94b174d088195b19ac1822f 100644
--- a/chrome/browser/net/pref_proxy_config_service.cc
+++ b/chrome/browser/net/pref_proxy_config_service.cc
@@ -38,13 +38,13 @@ void PrefProxyConfigTracker::DetachFromPrefService() {
 }
 
 void PrefProxyConfigTracker::AddObserver(
-    PrefProxyConfigTracker::ObserverInterface* observer) {
+    PrefProxyConfigTracker::Observer* observer) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
   observers_.AddObserver(observer);
 }
 
 void PrefProxyConfigTracker::RemoveObserver(
-    PrefProxyConfigTracker::ObserverInterface* observer) {
+    PrefProxyConfigTracker::Observer* observer) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
   observers_.RemoveObserver(observer);
 }
@@ -70,12 +70,11 @@ void PrefProxyConfigTracker::Observe(NotificationType type,
 void PrefProxyConfigTracker::InstallProxyConfig(const net::ProxyConfig& config,
                                                 bool valid) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
-  if (valid_ != valid || !pref_config_.Equals(config)) {
+  if (valid && (!valid_ || !pref_config_.Equals(config))) {

[eroman, 2010/12/02 19:31:22]

I don't think this is right, since it looks like we will never be able to return
to "use system settings (valid=false)".

I think what you want here instead is something like:

if (valid_ != valid || (valid && pref_config_.Equals(config))

Basically the only restriction we add is to avoid comparing config to
pref_config_ when !valid.

[eroman, 2010/12/02 19:32:40]

Oops my pseudo-code wasn't right either :-)
Let me try again:

if (valid_ != valid || (valid && !pref_config_.Equals(config))

[battre (please use the other), 2010/12/03 08:57:23]

Done.

     valid_ = valid;
     if (valid_)
       pref_config_ = config;
-    FOR_EACH_OBSERVER(ObserverInterface, observers_,
-                      OnPrefProxyConfigChanged());
+    FOR_EACH_OBSERVER(Observer, observers_, OnPrefProxyConfigChanged());
   }
 }
 
@@ -169,9 +168,11 @@ void PrefProxyConfigService::RemoveObserver(
 
 bool PrefProxyConfigService::GetLatestProxyConfig(net::ProxyConfig* config) {
   RegisterObservers();
-  const net::ProxyConfig pref_config;
-  if (pref_config_tracker_->GetProxyConfig(config))
+  net::ProxyConfig pref_config;
+  if (pref_config_tracker_->GetProxyConfig(&pref_config)) {
+    *config = pref_config;
     return true;
+  }
 
   return base_service_->GetLatestProxyConfig(config);
 }