Aura demo fix

ui/aura/demo/demo_main.cc

Index: ui/aura/demo/demo_main.cc
diff --git a/ui/aura/demo/demo_main.cc b/ui/aura/demo/demo_main.cc
index 7291c60cd0fbb8e726f6d1edffb228afba50d715..c4782b0fb320b1a45368b5569de9203bc620cb7e 100644
--- a/ui/aura/demo/demo_main.cc
+++ b/ui/aura/demo/demo_main.cc
@@ -11,7 +11,7 @@
 #include "ui/aura/client/stacking_client.h"
 #include "ui/aura/env.h"
 #include "ui/aura/event.h"
-#include "ui/aura/monitor_manager.h"
+#include "ui/aura/single_monitor_manager.h"
 #include "ui/aura/root_window.h"
 #include "ui/aura/window.h"
 #include "ui/aura/window_delegate.h"
@@ -111,7 +111,7 @@ int main(int argc, char** argv) {
   // Create the message-loop here before creating the root window.
   MessageLoop message_loop(MessageLoop::TYPE_UI);
   ui::CompositorTestSupport::Initialize();
-
+  aura::Env::GetInstance()->SetMonitorManager(new aura::SingleMonitorManager);
   scoped_ptr<aura::RootWindow> root_window(
       aura::MonitorManager::CreateRootWindowForPrimaryMonitor());
   scoped_ptr<DemoStackingClient> stacking_client(new DemoStackingClient(