Fix bug in changed_ranges

The order here matters!

src/tree.rs

@@ -1,4 +1,4 @@
-use emacs::{defun, Value, Result, Vector};
+use emacs::{defun, Result, Value, Vector};
 
 use tree_sitter::{InputEdit, Tree};
 
@@ -63,7 +63,7 @@ fn changed_ranges<'e>(tree: Value<'e>, old_tree: Borrowed<'e, Tree>) -> Result<V
     let env = tree.env;
     let tree = tree.into_rust::<Borrowed<Tree>>()?.borrow();
     let other_tree = old_tree.borrow();
-    let ranges = tree.changed_ranges(&*other_tree);
+    let ranges = other_tree.changed_ranges(&*tree);
     let vec = env.make_vector(ranges.len(), ())?;
     for (i, range) in ranges.enumerate() {
         vec.set(i, Range(range))?;