Move ProxyConfigService construction onto the IO thread.

chrome/browser/net/pref_proxy_config_tracker_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 "chrome/browser/net/pref_proxy_config_tracker_impl.h"
 
 #include "base/bind.h"
 #include "base/values.h"
 #include "chrome/browser/prefs/pref_service.h"
 #include "chrome/browser/prefs/pref_set_observer.h"
@@ skipping 52 matching lines @@
       pref_config_state_, pref_config_,
       system_availability, system_config, false,
       &config_state, config);
 }
 
 void ChromeProxyConfigService::OnLazyPoll() {
   if (base_service_.get())
     base_service_->OnLazyPoll();
 }
 
+void ChromeProxyConfigService::StartTearDown() {
+  if (base_service_.get())
+    base_service_->StartTearDown();
+}
+
 void ChromeProxyConfigService::UpdateProxyConfig(
     ProxyPrefs::ConfigState config_state,
     const net::ProxyConfig& config) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 
   pref_config_read_pending_ = false;
   pref_config_state_ = config_state;
   pref_config_ = config;
 
   if (!observers_.size())
@@ skipping 19 matching lines @@
     const net::ProxyConfig& config,
     ConfigAvailability availability) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 
   // Check whether there is a proxy configuration defined by preferences. In
   // this case that proxy configuration takes precedence and the change event
   // from the delegate proxy service can be disregarded.
   if (!PrefProxyConfigTrackerImpl::PrefPrecedes(pref_config_state_)) {
     net::ProxyConfig actual_config;
     availability = GetLatestProxyConfig(&actual_config);
-    FOR_EACH_OBSERVER(net::ProxyConfigService::Observer, observers_,
-                      OnProxyConfigChanged(actual_config, availability));
+    // Don't send out notification if we don't really have a configuration yet.
+    if (availability != net::ProxyConfigService::CONFIG_PENDING)
+      FOR_EACH_OBSERVER(net::ProxyConfigService::Observer, observers_,
+                        OnProxyConfigChanged(actual_config, availability));
   }
 }
 
 void ChromeProxyConfigService::RegisterObserver() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
   if (!registered_observer_ && base_service_.get()) {
     base_service_->AddObserver(this);
     registered_observer_ = true;
   }
 }
@@ skipping 212 matching lines @@
         config_state = ProxyPrefs::CONFIG_EXTENSION;
       else
         config_state = ProxyPrefs::CONFIG_OTHER_PRECEDE;
     } else  {
       config_state = ProxyPrefs::CONFIG_FALLBACK;
     }
   }
 
   return config_state;
 }