[Cronet] Hook up library loader, system proxy and network change notifier to async api.

components/cronet/android/url_request_context_adapter.cc

Index: components/cronet/android/url_request_context_adapter.cc
diff --git a/components/cronet/android/url_request_context_adapter.cc b/components/cronet/android/url_request_context_adapter.cc
index 6234aa942406bf4d04c058a78bde8298ad83f589..f056206151702d5cee0d6b2749f90671ac610738 100644
--- a/components/cronet/android/url_request_context_adapter.cc
+++ b/components/cronet/android/url_request_context_adapter.cc
@@ -30,12 +30,6 @@
 
 namespace {
 
-// MessageLoop on the main thread, which is where objects that receive Java
-// notifications generally live.
-base::MessageLoop* g_main_message_loop = nullptr;
-
-net::NetworkChangeNotifier* g_network_change_notifier = nullptr;
-
 class BasicNetworkDelegate : public net::NetworkDelegateImpl {
  public:
   BasicNetworkDelegate() {}
@@ -137,17 +131,6 @@ void URLRequestContextAdapter::Initialize(
 }
 
 void URLRequestContextAdapter::InitRequestContextOnMainThread() {
-  if (!base::MessageLoop::current()) {
-    DCHECK(!g_main_message_loop);
-    g_main_message_loop = new base::MessageLoopForUI();
-    base::MessageLoopForUI::current()->Start();
-  }
-  DCHECK_EQ(g_main_message_loop, base::MessageLoop::current());
-  if (!g_network_change_notifier) {
-    net::NetworkChangeNotifier::SetFactory(
-        new net::NetworkChangeNotifierFactoryAndroid());
-    g_network_change_notifier = net::NetworkChangeNotifier::Create();
-  }
   proxy_config_service_.reset(net::ProxyService::CreateSystemProxyConfigService(
       GetNetworkTaskRunner(), NULL));
   GetNetworkTaskRunner()->PostTask(