layout: Use FastTransform for hit testing (#38554)

`FastTransform` provides faster matrix operations when the involved
transforms are just translations.

Testing: Not needed (no change in behavior)

Signed-off-by: Oriol Brufau <obrufau@igalia.com>
Co-authored-by: Martin Robinson <mrobinson@igalia.com>

components/layout/display_list/stacking_context.rs

@@ -234,7 +234,7 @@ impl StackingContextTree {
                 origin,
                 frame_origin_for_query,
                 transform_style,
-                transform,
+                transform: transform.into(),
                 kind,
             }),
         )