Keep track of fixed positioning in accessibility tree.

ui/accessibility/ax_node.cc

Index: ui/accessibility/ax_node.cc
diff --git a/ui/accessibility/ax_node.cc b/ui/accessibility/ax_node.cc
index 8327ccd786e12e8ee052c220dd05f5192a128273..2b9b8f23a3062558d179b5f31cb105832d9c73df 100644
--- a/ui/accessibility/ax_node.cc
+++ b/ui/accessibility/ax_node.cc
@@ -32,13 +32,15 @@ void AXNode::SetData(const AXNodeData& src) {
 
 void AXNode::SetLocation(int offset_container_id,
                          const gfx::RectF& location,
-                         gfx::Transform* transform) {
+                         gfx::Transform* transform,
+                         bool is_fixed_positioned) {
   data_.offset_container_id = offset_container_id;
   data_.location = location;
   if (transform)
     data_.transform.reset(new gfx::Transform(*transform));
   else
     data_.transform.reset(nullptr);
+  data_.is_fixed_positioned = is_fixed_positioned;
 }
 
 void AXNode::SetIndexInParent(int index_in_parent) {