Reland of "Mustash: Ensure surfaces submitted to Mus by WM and embedders contain Surfaces with embe…

services/ui/ws/platform_display_delegate.h

 // Copyright 2015 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 SERVICES_UI_WS_PLATFORM_DISPLAY_DELEGATE_H_
 #define SERVICES_UI_WS_PLATFORM_DISPLAY_DELEGATE_H_
 
 namespace display {
 class Display;
 }
@@ skipping 10 matching lines @@
 // lifetime of a PlatformDisplay, forwards events to the appropriate windows,
 /// and responses to changes in viewport size.
 class PlatformDisplayDelegate {
  public:
   // Returns a display::Display for this display.
   virtual display::Display GetDisplay() = 0;
 
   // Returns the root window of this display.
   virtual ServerWindow* GetRootWindow() = 0;
 
+  // Returns the root window of the active user.
+  virtual ServerWindow* GetActiveRootWindow() = 0;
+
   // Called once when the AcceleratedWidget is available for drawing.
   virtual void OnAcceleratedWidgetAvailable() = 0;
 
   virtual bool IsInHighContrastMode() = 0;
 
   // Called when an event arrives.
   virtual void OnEvent(const ui::Event& event) = 0;
 
   // Called when the Display loses capture.
   virtual void OnNativeCaptureLost() = 0;
 
  protected:
   virtual ~PlatformDisplayDelegate() {}
 };
 
 }  // namespace ws
 
 }  // namespace ui
 
 #endif  // SERVICES_UI_WS_PLATFORM_DISPLAY_DELEGATE_H_