mus: Server-side implementation of modal windows

components/mus/ws/access_policy.h

 // Copyright 2014 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 COMPONENTS_MUS_WS_ACCESS_POLICY_H_
 #define COMPONENTS_MUS_WS_ACCESS_POLICY_H_
 
 #include <stdint.h>
 
 #include "components/mus/public/interfaces/mus_constants.mojom.h"
@@ skipping 15 matching lines @@
   // Unless otherwise mentioned all arguments have been validated. That is the
   // |window| arguments are non-null unless otherwise stated (eg CanSetWindow()
   // is allowed to take a NULL window).
   virtual bool CanRemoveWindowFromParent(const ServerWindow* window) const = 0;
   virtual bool CanAddWindow(const ServerWindow* parent,
                             const ServerWindow* child) const = 0;
   virtual bool CanAddTransientWindow(const ServerWindow* parent,
                                      const ServerWindow* child) const = 0;
   virtual bool CanRemoveTransientWindowFromParent(
       const ServerWindow* window) const = 0;
+  virtual bool CanSetAsModal(const ServerWindow* window) const = 0;
   virtual bool CanReorderWindow(const ServerWindow* window,
                                 const ServerWindow* relative_window,
                                 mojom::OrderDirection direction) const = 0;
   virtual bool CanDeleteWindow(const ServerWindow* window) const = 0;
   virtual bool CanGetWindowTree(const ServerWindow* window) const = 0;
   // Used when building a window tree (GetWindowTree()) to decide if we should
   // descend into |window|.
   virtual bool CanDescendIntoWindowForWindowTree(
       const ServerWindow* window) const = 0;
   virtual bool CanEmbed(const ServerWindow* window,
@@ skipping 23 matching lines @@
   // Returns the window to supply to the client when focus changes to |focused|.
   virtual const ServerWindow* GetWindowForFocusChange(
       const ServerWindow* focused) = 0;
 };
 
 }  // namespace ws
 
 }  // namespace mus
 
 #endif  // COMPONENTS_MUS_WS_ACCESS_POLICY_H_