Makes WindowTreeHost::InitHost() not Show the window

mash/simple_wm/simple_wm.cc

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "mash/simple_wm/simple_wm.h"
 
 #include "base/observer_list.h"
 #include "base/strings/utf_string_conversions.h"
 #include "ui/aura/client/aura_constants.h"
 #include "ui/aura/layout_manager.h"
@@ skipping 381 matching lines @@
                                      display::DisplayList::Type::PRIMARY);
 }
 
 void SimpleWM::OnWmNewDisplay(
     std::unique_ptr<aura::WindowTreeHostMus> window_tree_host,
     const display::Display& display) {
   // Only handles a single root.
   DCHECK(!window_root_);
   window_tree_host_ = std::move(window_tree_host);
   window_tree_host_->InitHost();
+  window_tree_host_->window()->Show();
   display_root_ = window_tree_host_->window();
   window_root_ = new aura::Window(nullptr);
   window_root_->Init(ui::LAYER_NOT_DRAWN);
   display_root_->AddChild(window_root_);
   window_root_->Show();
 
   window_list_model_ = base::MakeUnique<WindowListModel>(window_root_);
 
   views::Widget* window_list_widget = new views::Widget;
   views::NativeWidgetAura* window_list_widget_native_widget =
@@ skipping 55 matching lines @@
   return it != client_window_to_frame_view_.end() ? it->second : nullptr;
 }
 
 void SimpleWM::OnWindowListViewItemActivated(aura::Window* window) {
   aura::client::ActivationClient* activation_client =
       aura::client::GetActivationClient(window->GetRootWindow());
   activation_client->ActivateWindow(window);
 }
 
 }  // namespace simple_wm