Reorder the NativeViews attached to a view via kViewHostKey according to the position of the view

ui/views/view.cc

 // Copyright (c) 2012 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.
 
 #define _USE_MATH_DEFINES // For VC++ to get M_PI. This has to be first.
 
 #include "ui/views/view.h"
 
 #include <algorithm>
 #include <cmath>
@@ skipping 1421 matching lines @@
 
 base::Closure View::PrepareForLayerBoundsChange() {
   return base::Closure();
 }
 
 void View::ReorderLayers() {
   View* v = this;
   while (v && !v->layer())
     v = v->parent();
 
-  // Forward to widget in case we're in a NativeWidgetAura.
-  if (!v) {
-    if (GetWidget())
+  if (GetWidget()) {

[sky, 2013/05/23 15:36:49]

cache call to GetWidget

+    // If the widget has a view with an attached NativeView (eg NativeViewHost),
+    // the widget's layers must be reordered. The attached NativeView's layer is
+    // always parented to the widget's layer regardless of whether the host view
+    // has an ancestor view with a layer.
+    if (!v || GetWidget()->HasNativeViewAttachedToViewTree())

[sky, 2013/05/23 15:36:49]

HasNativeViewAttachedToViewTree doesn't make sense for windows.

I think a better approach here is to always call GetWidget()->ReorderLayers(v):

void Widget::ReorderLayers(View* parent_with_layer) {
  if (!parent_width_layer && native_widget_->GetLayer())
    root_view_->ReorderChildLayers(native_widget_->GetLayer());
  if (native_widget_->ShouldReorderViewsWithLayers(parent_with_layer))
    // call off to your new function here.
}

GetLayer() is a new method in NativeWidgetPrivate. It replaces
CalculateOffsetToAncestorWithLayer() which doesn't make sense anymore.

ShouldReorderViewsWithLayers is effectively what you have in
HasNativeViewAttachedToViewTree.

I also think this (WIdget::ReorderLayers) should be invoked after the children
are reordered. That way the view layers are all ordered correctly when you
attempt to reorder for the NativeViewHosts.

       GetWidget()->ReorderLayers();
-  } else {
+  }
+  if (v) {
     for (Views::const_iterator i(v->children_.begin());
          i != v->children_.end();
          ++i)
       (*i)->ReorderChildLayers(v->layer());
   }
 }
 
 void View::ReorderChildLayers(ui::Layer* parent_layer) {
   if (layer()) {
     DCHECK_EQ(parent_layer, layer()->parent());
@@ skipping 841 matching lines @@
   ConvertPointToWidget(this, &widget_location);
   GetWidget()->RunShellDrag(this, data, widget_location, drag_operations,
       source);
   return true;
 #else
   return false;
 #endif  // !defined(OS_MACOSX)
 }
 
 }  // namespace views