c44dd17d47
Previously, we'd leave the old values in the parent data if the types matches, but not all render objects would reset these values during layout. For example, RenderProxyBox doesn't set the position field because it doesn't read the position field. However, leaving the old data there violates the invariants of the box protocol and can cause trouble (e.g., localToGlobal giving the wrong result). Fixes #1939