Use relative bounding boxes throughout Chrome accessibility

ui/accessibility/ax_tree_combiner.cc

 // Copyright 2016 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/accessibility/ax_tree.h"
 #include "ui/accessibility/ax_tree_combiner.h"
 #include "ui/gfx/geometry/rect_f.h"
 
 namespace ui {
 namespace {
@@ skipping 167 matching lines @@
     AXNodeData node = tree->nodes[i];
     int32_t child_tree_id = node.GetIntAttribute(AX_ATTR_CHILD_TREE_ID);
 
     // Map the node's ID.
     node.id = MapId(tree_id, node.id);
 
     // Map the node's child IDs.
     for (size_t j = 0; j < node.child_ids.size(); ++j)
       node.child_ids[j] = MapId(tree_id, node.child_ids[j]);
 
+    // Reset the offset container ID because we make all bounding boxes
+    // absolute.
+    node.offset_container_id = -1;
+
     // Map other int attributes that refer to node IDs, and remove the
     // AX_ATTR_CHILD_TREE_ID attribute.
     for (size_t j = 0; j < node.int_attributes.size(); ++j) {
       auto& attr = node.int_attributes[j];
       if (IsNodeIdIntAttribute(attr.first))
         attr.second = MapId(tree_id, attr.second);
       if (attr.first == AX_ATTR_CHILD_TREE_ID) {
         attr.first = AX_INT_ATTRIBUTE_NONE;
         attr.second = 0;
       }
@@ skipping 33 matching lines @@
     // Recurse into the child tree now, if any.
     if (child_tree)
       ProcessTree(child_tree);
   }
 
   // Reset the transform.
   transform_ = old_transform;
 }
 
 }  // namespace ui