* Run pub get before building host.dart. * We should call `pub get` for `web_ui` in the launcher script because felt itself needs it. However, we should let felt invoke `pub get` on `web_engine_tester` only as needed, not in the launcher script.
* Run pub get before building host.dart. * We should call `pub get` for `web_ui` in the launcher script because felt itself needs it. However, we should let felt invoke `pub get` on `web_engine_tester` only as needed, not in the launcher script.