Wires up transient windows for aura-mus

ui/aura/mus/window_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_AURA_MUS_WINDOW_MUS_H_
 #define UI_AURA_MUS_WINDOW_MUS_H_
 
 #include <stdint.h>
 
 #include <string>
@@ skipping 27 matching lines @@
 
 // WindowMus defines the interface used by WindowTreeClient to modify
 // the underlying Window. It's defined as a separate interface to make it clear
 // that any changes that WindowTreeClient makes must be propagated through
 // this interface so that they don't result in bouncing back to
 // WindowTreeClient. For example, if the server change the bounds care must be
 // taken that when the change is applied to the Window the server isn't asked to
 // change the bounds too. See WindowPortMus for details.
 class AURA_EXPORT WindowMus {
  public:
+
+  enum class ChangeSource {
+    // The change was made locally.
+    LOCAL,
+    // The change originated from the server.
+    SERVER,
+  };
+
   // |create_remote_window| indicates whether a window should be created on the
   // server. Generally |create_remote_window| should be true, only in rare
   // exceptions (such as the root of a WindowTreeHost) is it false.
   explicit WindowMus(bool create_remote_window)
       : create_remote_window_(create_remote_window) {}
   virtual ~WindowMus() {}
 
   // Returns the WindowMus associated with |window|.
   static WindowMus* Get(Window* window);
 
@@ skipping 20 matching lines @@
                                  WindowMus* relative,
                                  ui::mojom::OrderDirection) = 0;
   virtual void SetBoundsFromServer(const gfx::Rect& bounds) = 0;
   virtual void SetVisibleFromServer(bool visible) = 0;
   virtual void SetOpacityFromServer(float opacity) = 0;
   virtual void SetPredefinedCursorFromServer(ui::mojom::Cursor cursor) = 0;
   virtual void SetPropertyFromServer(const std::string& property_name,
                                      const std::vector<uint8_t>* data) = 0;
   virtual void SetSurfaceIdFromServer(
       std::unique_ptr<SurfaceInfo> surface_info) = 0;
+  virtual void AddTransientChildFromServer(WindowMus* child) = 0;
+  virtual void RemoveTransientChildFromServer(WindowMus* child) = 0;
+  // Called when a window was added/removed as a transient child.
+  virtual ChangeSource OnTransientChildAdded(WindowMus* child) = 0;
+  virtual ChangeSource OnTransientChildRemoved(WindowMus* child) = 0;
 
   // Called in the rare case when WindowTreeClient needs to change state and
   // can't go through one of the SetFooFromServer() functions above. Generally
   // because it needs to call another function that as a side effect changes the
   // window. Once the call to the underlying window has completed the returned
   // object should be destroyed.
   virtual std::unique_ptr<WindowMusChangeData> PrepareForServerBoundsChange(
       const gfx::Rect& bounds) = 0;
   virtual std::unique_ptr<WindowMusChangeData> PrepareForServerVisibilityChange(
       bool value) = 0;
 
   virtual void NotifyEmbeddedAppDisconnected() = 0;
 
  private:
   // Just for set_server_id(), which other places should not call.
   friend class WindowTreeClient;
 
   void set_server_id(Id id) { server_id_ = id; }
 
   Id server_id_ = kInvalidServerId;
   const bool create_remote_window_;
 };
 
 }  // namespace aura
 
 #endif  // UI_AURA_MUS_WINDOW_MUS_H_