MacViews: Reattach children of native windows when they are exposed.

ui/views/cocoa/bridged_native_widget.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 UI_VIEWS_COCOA_BRIDGED_NATIVE_WIDGET_H_
 #define UI_VIEWS_COCOA_BRIDGED_NATIVE_WIDGET_H_
 
 #import <Cocoa/Cocoa.h>
 
 #include <memory>
@@ skipping 175 matching lines @@
 
   // The parent widget specified in Widget::InitParams::parent. If non-null, the
   // parent will close children before the parent closes, and children will be
   // raised above their parent when window z-order changes.
   BridgedNativeWidgetOwner* parent() { return parent_; }
   const std::vector<BridgedNativeWidget*>& child_windows() {
     return child_windows_;
   }
 
   bool target_fullscreen_state() const { return target_fullscreen_state_; }
-  bool window_visible() { return window_visible_; }
+  bool window_visible() const { return window_visible_; }
+  bool wants_to_be_visible() const { return wants_to_be_visible_; }
 
   // Overridden from ui::internal::InputMethodDelegate:
   ui::EventDispatchDetails DispatchKeyEventPostIME(ui::KeyEvent* key) override;
 
  private:
   friend class test::BridgedNativeWidgetTestApi;
 
   // Closes all child windows. BridgedNativeWidget children will be destroyed.
   void RemoveOrDestroyChildren();
 
@@ skipping 112 matching lines @@
   bool initial_visibility_suppressed_ = false;
 
   AssociatedViews associated_views_;
 
   DISALLOW_COPY_AND_ASSIGN(BridgedNativeWidget);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_COCOA_BRIDGED_NATIVE_WIDGET_H_