I4212ac327a moved gwt-dev transitive dependencies to first order
dependencies, but broke eclipse project generation, as javax
validation is still needed. If47aad9d7 tried to fix it and added
dependency to the missing library, but missed to add a dependency
to the sources as well to fix SDM debug session.
Test plan:
SDM debug session works as expected.
Change-Id: I9cc4ebe60b38c0a38006a6f08c9d70415a7a100c