fix selection test expectation

src/browser/tests/selection.html

@@ -412,7 +412,7 @@
     // Should end at offset equal to number of children (after last child)
     testing.expectEqual(childrenCount, sel.focusOffset);
 
-    // Direction should be none
+    // Direction should be forward
     testing.expectEqual("forward", sel.direction);
 
     // Should not fully contain the parent itself