Fix scrolling offset of preedit window

widget/src/scrollable.rs

@@ -753,7 +753,7 @@ where
                     if let InputMethod::Open { position, .. } =
                         shell.input_method_mut()
                     {
-                        *position = *position + translation;
+                        *position = *position - translation;
                     }
                 }
             };