I was able to get it done while pair programming with Claude.
Claude does well with Java and GWT. It works best when it can look at your project structure and add features that are not conceptually difficult but are tedious, especially accounting for edge cases. Its able to even understand and flawlessly add or refactor changes to UiBinder.
I plan to release this on GitHub once its done..need to add a DataSource and the ability to have editors. But please let me know if anyone is interested in a component like this.