views: Some more layer change, and add/update some tests for layers.

views/controls/native_control_gtk.cc

 // Copyright (c) 2011 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.
 
 #include "views/controls/native_control_gtk.h"
 
 #include <gtk/gtk.h>
 
 #include "base/logging.h"
 #include "ui/base/accessibility/accessibility_types.h"
@@ skipping 154 matching lines @@
   if (!is_add && child == this && native_view()) {
     Detach();
   } else if (is_add && GetWidget() && !native_view()) {
     // Create the widget when we're added to a valid Widget. Many
     // controls need a parent widget to function properly.
     CreateNativeControl();
   }
 }
 
 void NativeControlGtk::VisibilityChanged(View* starting_from, bool is_visible) {
+  if (starting_from != this)
+    return;

[oshima, 2011/10/10 08:10:09]

I first thought this isn't correct (because you need to hide native widget when
parent view is invisible), but looking at code more closely, the code has
changed recently and Detach no longer *detach* the widget. Honestly I don't
understand why this works. Could be that we just happen to not have such use
case because there is far less native view used in the browser, but I may be
wrong. Let me talk to dave first and will get back to you.

   if (!is_visible) {
     if (native_view()) {
       // We destroy the child widget when we become invisible because of the
       // performance cost of maintaining widgets that aren't currently needed.
       Detach();
       // Make sure that Detach destroyed the widget.
       DCHECK(!native_view());
     }
   } else if (!native_view()) {
     if (GetWidget())
@@ skipping 57 matching lines @@
     // options page is only based on views.
     // NOTREACHED();
     NOTIMPLEMENTED();
     return false;
   }
   focus_manager->SetFocusedView(control->focus_view());
   return false;
 }
 
 }  // namespace views