Move ProxyConfigService construction onto the IO thread.

chrome/browser/io_thread.cc

Index: chrome/browser/io_thread.cc
diff --git a/chrome/browser/io_thread.cc b/chrome/browser/io_thread.cc
index b8b3c9000033954a6e31e17ec8dee9cba1930b1b..76ac6fbd3e13697992b4ef7bf77899e91014db9c 100644
--- a/chrome/browser/io_thread.cc
+++ b/chrome/browser/io_thread.cc
@@ -379,8 +379,7 @@ IOThread::~IOThread() {
   // be multiply constructed.
   BrowserThread::SetDelegate(BrowserThread::IO, NULL);
 
-  if (pref_proxy_config_tracker_.get())
-    pref_proxy_config_tracker_->DetachFromPrefService();
+  pref_proxy_config_tracker_->DetachFromPrefService();
   DCHECK(!globals_);
 }
 
@@ -536,6 +535,8 @@ void IOThread::Init() {
   globals_->proxy_script_fetcher_context.reset(
       ConstructProxyScriptFetcherContext(globals_, net_log_));
 
+  system_proxy_config_service_.reset(
+      ProxyServiceFactory::CreateProxyConfigService(true));
   sdch_manager_ = new net::SdchManager();
 
 #if defined(OS_MACOSX) && !defined(OS_IOS)
@@ -674,14 +675,8 @@ void IOThread::InitSystemRequestContext() {
   // If we're in unit_tests, IOThread may not be run.
   if (!BrowserThread::IsMessageLoopValid(BrowserThread::IO))
     return;
-  bool wait_for_first_update = (pref_proxy_config_tracker_.get() != NULL);
-  ChromeProxyConfigService* proxy_config_service =
-      ProxyServiceFactory::CreateProxyConfigService(wait_for_first_update);
-  system_proxy_config_service_.reset(proxy_config_service);
-  if (pref_proxy_config_tracker_.get()) {
-    pref_proxy_config_tracker_->SetChromeProxyConfigService(
-        proxy_config_service);
-  }
+  pref_proxy_config_tracker_->SetChromeProxyConfigService(
+      system_proxy_config_service_.get());
   system_url_request_context_getter_ =
       new SystemURLRequestContextGetter(this);
   // Safe to post an unretained this pointer, since IOThread is
@@ -737,3 +732,8 @@ void IOThread::InitSystemRequestContextOnIOThread() {
   sdch_manager_->set_sdch_fetcher(
       new SdchDictionaryFetcher(system_url_request_context_getter_.get()));
 }
+
+void IOThread::StartTearDown() {
+  globals_->system_proxy_service->StartTearDown();
+}
+