Adds a factory function to ViewsDelegate for DesktopWindowTreeHost

ui/views/views_delegate.h

 // Copyright (c) 2012 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_VIEWS_DELEGATE_H_
 #define UI_VIEWS_VIEWS_DELEGATE_H_
 
+#include <memory>
 #include <string>
 
 #if defined(OS_WIN)
 #include <windows.h>
 #endif
 
 #include "base/callback.h"
 #include "base/location.h"
 #include "base/macros.h"
 #include "base/strings/string16.h"
@@ skipping 26 matching lines @@
 
 namespace views {
 
 class NativeWidget;
 class NonClientFrameView;
 class ViewsTouchEditingControllerFactory;
 class View;
 class Widget;
 
 #if defined(USE_AURA)
+class DesktopNativeWidgetAura;
+class DesktopWindowTreeHost;
 class TouchSelectionMenuRunnerViews;
 #endif
 
 namespace internal {
 class NativeWidgetDelegate;
 }
 
 enum class InsetsMetric {
   // The margins that should be applied around a bubble dialog.
   BUBBLE_DIALOG,
@@ skipping 27 matching lines @@
 // framework. It is used to obtain various high level application utilities
 // and perform some actions such as window placement saving.
 //
 // The embedding app must set the ViewsDelegate instance by instantiating an
 // implementation of ViewsDelegate (the constructor will set the instance).
 class VIEWS_EXPORT ViewsDelegate {
  public:
   using NativeWidgetFactory =
       base::Callback<NativeWidget*(const Widget::InitParams&,
                                    internal::NativeWidgetDelegate*)>;
+#if defined(USE_AURA)
+  using DesktopWindowTreeHostFactory =
+      base::Callback<std::unique_ptr<DesktopWindowTreeHost>(
+          const Widget::InitParams&,
+          internal::NativeWidgetDelegate*,
+          DesktopNativeWidgetAura*)>;
+#endif
+
 #if defined(OS_WIN)
   enum AppbarAutohideEdge {
     EDGE_TOP    = 1 << 0,
     EDGE_LEFT   = 1 << 1,
     EDGE_BOTTOM = 1 << 2,
     EDGE_RIGHT  = 1 << 3,
   };
 #endif
 
   enum class ProcessMenuAcceleratorResult {
     // The accelerator was handled while the menu was showing. No further action
     // is needed and the menu should be kept open.
     LEAVE_MENU_OPEN,
 
     // The accelerator was not handled. Menu should be closed and the
     // accelerator will be reposted to be handled after the menu closes.
     CLOSE_MENU
   };
 
   virtual ~ViewsDelegate();
 
   // Returns the ViewsDelegate instance if there is one, or nullptr otherwise.
   static ViewsDelegate* GetInstance();
 
   // Call this method to set a factory callback that will be used to construct
   // NativeWidget implementations overriding the platform defaults.
-  void set_native_widget_factory(NativeWidgetFactory factory) {
+  void set_native_widget_factory(const NativeWidgetFactory& factory) {
     native_widget_factory_ = factory;
   }
-  const NativeWidgetFactory& native_widget_factory() {
+  const NativeWidgetFactory& native_widget_factory() const {
     return native_widget_factory_;
   }
 
+#if defined(USE_AURA)
+  void set_desktop_window_tree_host_factory(
+      const DesktopWindowTreeHostFactory& factory) {
+    desktop_window_tree_host_factory_ = factory;
+  }
+  const DesktopWindowTreeHostFactory& desktop_window_tree_host_factory() const {
+    return desktop_window_tree_host_factory_;
+  }
+#endif
   // Saves the position, size and "show" state for the window with the
   // specified name.
   virtual void SaveWindowPlacement(const Widget* widget,
                                    const std::string& window_name,
                                    const gfx::Rect& bounds,
                                    ui::WindowShowState show_state);
 
   // Retrieves the saved position and size and "show" state for the window with
   // the specified name.
   virtual bool GetSavedWindowPlacement(const Widget* widget,
@@ skipping 89 matching lines @@
   virtual int GetDistanceMetric(DistanceMetric metric) const;
 
  protected:
   ViewsDelegate();
 
  private:
   std::unique_ptr<ViewsTouchEditingControllerFactory> views_tsc_factory_;
 
 #if defined(USE_AURA)
   std::unique_ptr<TouchSelectionMenuRunnerViews> touch_selection_menu_runner_;
+
+  DesktopWindowTreeHostFactory desktop_window_tree_host_factory_;
 #endif
 
   NativeWidgetFactory native_widget_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(ViewsDelegate);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_VIEWS_DELEGATE_H_