Adds OnChildWindowVisibilityChanged to ui::WindowObserver

services/ui/public/cpp/window.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 SERVICES_UI_PUBLIC_CPP_WINDOW_H_
 #define SERVICES_UI_PUBLIC_CPP_WINDOW_H_
 
 #include <stdint.h>
 #include <vector>
 
@@ skipping 296 matching lines @@
   void LocalSetVisible(bool visible);
   void LocalSetOpacity(float opacity);
   void LocalSetPredefinedCursor(mojom::Cursor cursor_id);
   void LocalSetSharedProperty(const std::string& name,
                               const std::vector<uint8_t>* data);
 
   // Notifies this winodw that its stacking position has changed.
   void NotifyWindowStackingChanged();
   // Methods implementing visibility change notifications. See WindowObserver
   // for more details.
-  void NotifyWindowVisibilityChanged(Window* target);
+  void NotifyWindowVisibilityChanged(Window* target, bool visible);
   // Notifies this window's observers. Returns false if |this| was deleted
   // during the call (by an observer), otherwise true.
-  bool NotifyWindowVisibilityChangedAtReceiver(Window* target);
+  bool NotifyWindowVisibilityChangedAtReceiver(Window* target, bool visible);
   // Notifies this window and its child hierarchy. Returns false if |this| was
   // deleted during the call (by an observer), otherwise true.
-  bool NotifyWindowVisibilityChangedDown(Window* target);
+  bool NotifyWindowVisibilityChangedDown(Window* target, bool visible);
   // Notifies this window and its parent hierarchy.
-  void NotifyWindowVisibilityChangedUp(Window* target);
+  void NotifyWindowVisibilityChangedUp(Window* target, bool visible);
 
   // Returns true if embed is allowed for this node. If embedding is allowed all
   // the children are removed.
   bool PrepareForEmbed();
 
   void RemoveTransientWindowImpl(Window* child);
   static void ReorderWithoutNotification(Window* window,
                                          Window* relative,
                                          mojom::OrderDirection direction);
   static bool ReorderImpl(Window* window,
@@ skipping 55 matching lines @@
   };
 
   std::map<const void*, Value> prop_map_;
 
   DISALLOW_COPY_AND_ASSIGN(Window);
 };
 
 }  // namespace ui
 
 #endif  // SERVICES_UI_PUBLIC_CPP_WINDOW_H_