Enables passing initial properties to top level window creation

ui/views/mus/desktop_window_tree_host_mus.h

 // 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.
 
 #ifndef UI_VIEWS_WIDGET_DESKTOP_AURA_DESKTOP_WINDOW_TREE_HOST_MUS_H_
 #define UI_VIEWS_WIDGET_DESKTOP_AURA_DESKTOP_WINDOW_TREE_HOST_MUS_H_
 
 #include <memory>
 #include <set>
 
 #include "base/macros.h"
 #include "ui/aura/env_observer.h"
 #include "ui/aura/mus/window_tree_host_mus.h"
 #include "ui/views/mus/mus_export.h"
 #include "ui/views/widget/desktop_aura/desktop_window_tree_host.h"
+#include "ui/views/widget/widget.h"
 
 namespace views {
 
 class VIEWS_MUS_EXPORT DesktopWindowTreeHostMus
     : public DesktopWindowTreeHost,
       public aura::WindowTreeHostMus,
       public aura::EnvObserver {
  public:
   DesktopWindowTreeHostMus(
       internal::NativeWidgetDelegate* native_widget_delegate,
-      DesktopNativeWidgetAura* desktop_native_widget_aura);
+      DesktopNativeWidgetAura* desktop_native_widget_aura,
+      const Widget::InitParams& init_params);
   ~DesktopWindowTreeHostMus() override;
 
  private:
   bool IsDocked() const;
 
   // DesktopWindowTreeHost:
   void Init(aura::Window* content_window,
             const Widget::InitParams& params) override;
   void OnNativeWidgetCreated(const Widget::InitParams& params) override;
   std::unique_ptr<corewm::Tooltip> CreateTooltip() override;
@@ skipping 80 matching lines @@
 
   // Used so that Close() isn't immediate.
   base::WeakPtrFactory<DesktopWindowTreeHostMus> close_widget_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(DesktopWindowTreeHostMus);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_WIDGET_DESKTOP_AURA_DESKTOP_WINDOW_TREE_HOST_MUS_H_