Keep track of fixed positioning in accessibility tree.

third_party/WebKit/Source/modules/exported/WebAXObject.cpp

Index: third_party/WebKit/Source/modules/exported/WebAXObject.cpp
diff --git a/third_party/WebKit/Source/modules/exported/WebAXObject.cpp b/third_party/WebKit/Source/modules/exported/WebAXObject.cpp
index 591c8f3e80dd9aeb24bb58cc6073efc4e6125eb6..dc73cbb7f0afba213f0617faaf78ca82c81cb59a 100644
--- a/third_party/WebKit/Source/modules/exported/WebAXObject.cpp
+++ b/third_party/WebKit/Source/modules/exported/WebAXObject.cpp
@@ -1507,7 +1507,8 @@ void WebAXObject::SetScrollOffset(const WebPoint& offset) const {
 
 void WebAXObject::GetRelativeBounds(WebAXObject& offset_container,
                                     WebFloatRect& bounds_in_container,
-                                    SkMatrix44& container_transform) const {
+                                    SkMatrix44& container_transform,
+                                    bool& is_fixed_positioned) const {
   if (IsDetached())
     return;
 
@@ -1517,7 +1518,8 @@ void WebAXObject::GetRelativeBounds(WebAXObject& offset_container,
 
   AXObject* container = nullptr;
   FloatRect bounds;
-  private_->GetRelativeBounds(&container, bounds, container_transform);
+  private_->GetRelativeBounds(&container, bounds, container_transform,
+                              is_fixed_positioned);
   offset_container = WebAXObject(container);
   bounds_in_container = WebFloatRect(bounds);
 }