[ash-md] Adds support for Z-order iteration in views::View

ui/views/view_targeter_delegate.cc

 // 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.
 
 #include "ui/views/view_targeter_delegate.h"
 
 #include <limits.h>
 
 #include "ui/gfx/geometry/rect_conversions.h"
 #include "ui/views/rect_based_targeting_utils.h"
@@ skipping 24 matching lines @@
   // |rect_view_distance| is used to keep track of the distance
   // between the center point of |rect_view| and the center
   // point of |rect|.
   View* rect_view = NULL;
   int rect_view_distance = INT_MAX;
 
   // |point_view| represents the view that would have been returned
   // from this function call if point-based targeting were used.
   View* point_view = NULL;
 
-  for (int i = root->child_count() - 1; i >= 0; --i) {
-    View* child = root->child_at(i);
-
+  View::Views children = root->GetChildrenOrderedByVisualOrder();
+  DCHECK_EQ(root->child_count(), static_cast<int>(children.size()));
+  for (int i = children.size() - 1; i >= 0; --i) {
+    View* child = children[i];
     if (!child->CanProcessEventsWithinSubtree())
       continue;
 
     // Ignore any children which are invisible or do not intersect |rect|.
     if (!child->visible())
       continue;
     gfx::RectF rect_in_child_coords_f(rect);
     View::ConvertRectToTarget(root, child, &rect_in_child_coords_f);
     gfx::Rect rect_in_child_coords = gfx::ToEnclosingRect(
         rect_in_child_coords_f);
@@ skipping 39 matching lines @@
     int cur_dist = views::DistanceSquaredFromCenterToPoint(touch_center,
                                                            local_bounds);
     if (!rect_view || cur_dist < rect_view_distance)
       rect_view = root;
   }
 
   return rect_view ? rect_view : point_view;
 }
 
 }  // namespace views