Move ProxyConfigService construction onto the IO thread.

chrome/browser/net/proxy_service_factory.cc

Index: chrome/browser/net/proxy_service_factory.cc
diff --git a/chrome/browser/net/proxy_service_factory.cc b/chrome/browser/net/proxy_service_factory.cc
index 2cdd496bbf8a63df70e42e7bc103b1c5b9c3277d..9842fcbc89dcf0d72983092b172ca4ca7d9fca77 100644
--- a/chrome/browser/net/proxy_service_factory.cc
+++ b/chrome/browser/net/proxy_service_factory.cc
@@ -29,9 +29,7 @@ using content::BrowserThread;
 // static
 ChromeProxyConfigService* ProxyServiceFactory::CreateProxyConfigService(
     bool wait_for_first_update) {
-  // The linux gconf-based proxy settings getter relies on being initialized
-  // from the UI thread.
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 
   net::ProxyConfigService* base_service = NULL;
 
@@ -48,7 +46,7 @@ ChromeProxyConfigService* ProxyServiceFactory::CreateProxyConfigService(
   // that code be moved to chrome/browser instead of being in net, so that it
   // can use BrowserThread instead of raw MessageLoop pointers? See bug 25354.
   base_service = net::ProxyService::CreateSystemProxyConfigService(
-      BrowserThread::GetMessageLoopProxyForThread(BrowserThread::IO),
+      BrowserThread::GetMessageLoopProxyForThread(BrowserThread::UI),
       BrowserThread::UnsafeGetMessageLoopForThread(BrowserThread::FILE));
 #endif  // !defined(OS_CHROMEOS)