changelog for callback graph robustness fix

Author: alexcjohnson

CHANGELOG.md

@@ -5,6 +5,7 @@ This project adheres to [Semantic Versioning](https://semver.org/).
 ## Unreleased
 ### Fixed
 - [#1415](https://github.com/plotly/dash/pull/1415) Fix a regression with some layouts callbacks involving dcc.Tabs, not yet loaded dash_table.DataTable and dcc.Graph to not be called
+- [#1416](https://github.com/plotly/dash/pull/1416) Make callback graph more robust for complex apps and some specific props (`width` in particular) that previously caused errors.
 
 ## [1.16.1] - 2020-09-16
 ### Changed