Auto merge of #18212 - mrobinson:position-sticky, r=emilio

Add support for position:sticky

This leverages the position:sticky support in WebRender to bring basic
support for position:sticky in Servo. There are still some issues with
nested sticky flows as well as a few other corner cases. Tests are
imported from WPT and can be removed once we update to the latest
version.

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- [ ] These changes fix #__ (github issue number if applicable).

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1 files changed, 1 insertions, 1 deletions

diff --git a/components/layout/sequential.rs b/components/layout/sequential.rs
index ef57d1d402c..6673ecc8e14 100644
--- a/components/layout/sequential.rs
+++ b/components/layout/sequential.rs
@@ -93,7 +93,7 @@ pub fn iterate_through_flow_tree_fragment_border_boxes(root: &mut Flow, iterator
                                             flow::base(kid).stacking_relative_position +
                                             stacking_context_position.to_vector();
                 let relative_position = kid.as_block()
-                    .stacking_relative_position(CoordinateSystem::Own);
+                    .stacking_relative_border_box(CoordinateSystem::Own);
                 if let Some(matrix) = kid.as_block()
                        .fragment
                        .transform_matrix(&relative_position) {