Makes WindowTreeHost::InitHost() not Show the window

ash/display/mirror_window_controller.cc

Index: ash/display/mirror_window_controller.cc
diff --git a/ash/display/mirror_window_controller.cc b/ash/display/mirror_window_controller.cc
index 8d48cfd917421cc73d8bc7bb29b245a80bf65bd6..66c0d86dcfd4a0530e0b4b23f74d516451ee0a29 100644
--- a/ash/display/mirror_window_controller.cc
+++ b/ash/display/mirror_window_controller.cc
@@ -192,6 +192,7 @@ void MirrorWindowController::UpdateWindow(
       // TODO(oshima): TouchHUD is using idkey.
       InitRootWindowSettings(host->window())->display_id = display_info.id();
       host->InitHost();
+      host->window()->Show();
 #if defined(USE_X11)
       if (!display_manager->IsInUnifiedMode()) {
         // Mirror window shouldn't handle input events.