MacViews: Attach child windows when parent is on the screen.

ui/views/cocoa/bridged_native_widget.h

 // Copyright 2014 The Chromium Authors. All rights reserved.

[tapted, 2016/06/30 12:02:37]

cl description should go something like

"""MacViews: Ensure child windows are only managed with real changes to
-[NSWindow isVisible].

MacViews: Ensure child windows are only managed with real changes to -[NSWindow
isVisible].

After restoring from a miniaturize, child windows are currently reattached too
early. This is because AppKit draws the window before updating the result of
-[NSWindow isVisible], and we need to participate in that draw. But updating
child window relationships at this time causes layering issues when the window
has finished restoring.

Instead, wait until -[NSWindow isVisible] becomes YES.
"""


make sure it's wrapped at < 80 chars.

 // 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>
 #include <vector>
@@ skipping 112 matching lines @@
   void ToggleDesiredFullscreenState();
 
   // Called by the NSWindowDelegate when the size of the window changes.
   void OnSizeChanged();
 
   // Called by the NSWindowDelegate when the visibility of the window may have
   // changed. For example, due to a (de)miniaturize operation, or the window
   // being reordered in (or out of) the screen list.
   void OnVisibilityChanged();
 
-  // Explicitly set the visibility. This is called when Cocoa requests a draw,
-  // but hasn't updated the value of -[NSWindow isVisible] yet.
-  void OnVisibilityChangedTo(bool new_visibility);
-
   // Called by the NSWindowDelegate on a scale factor or color space change.
   void OnBackingPropertiesChanged();
 
   // Called by the NSWindowDelegate when the window becomes or resigns key.
   void OnWindowKeyStatusChangedTo(bool is_key);
 
   // Called by NSWindowDelegate when the application receives a mouse-down, but
   // before the event is processed by NSWindows. Returning true here will cause
   // the event to be cancelled and reposted at the CGSessionEventTap level. This
   // is used to determine whether a mouse-down should drag the window.
@@ skipping 155 matching lines @@
   bool invalidate_shadow_on_frame_swap_ = false;
 
   AssociatedViews associated_views_;
 
   DISALLOW_COPY_AND_ASSIGN(BridgedNativeWidget);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_COCOA_BRIDGED_NATIVE_WIDGET_H_