refactor!: Be opinionated about coordinates after all (#151)

Author: mwcampbell

common/src/lib.rs

@@ -667,15 +667,9 @@ pub struct Node {
     /// if it would be set to the identity transform, which should be
     /// the case for most nodes.
     ///
-    /// AccessKit is not opinionated about the resolution dependence
-    /// or y direction of any coordinates; these requirements are
-    /// ultimately determined by the platform accessibility API.
-    /// This implies that for a tree generated by cross-platform code,
-    /// a platform-specific layer between that cross-platform code
-    /// and the AccessKit platform adapter must add an appropriate transform to
-    /// the root node. However, AccessKit expects the final transformed
-    /// coordinates to be relative to the origin of the tree's container
-    /// (e.g. window).
+    /// AccessKit expects the final transformed coordinates to be relative
+    /// to the origin of the tree's container (e.g. window), in physical
+    /// pixels, with the y coordinate being top-down.
     ///
     /// [`bounds`]: Node::bounds
     #[cfg_attr(feature = "serde", serde(skip_serializing_if = "Option::is_none"))]