I get this on every page when I single-step in observatory. I think `DebuggerFrameElement._varsDiv` should be nullable, not `late`. The value is tested for null. ``` Unexpected exception: LateInitializationError: Field '_varsDiv' has not been initialized. StackTrace: main.dart.js 466:3 Object.f main.dart.js 473:23 Object.b main.dart.js 28446:39 en.gkB main.dart.js 28607:13 en.zX main.dart.js 1:1 Object.eval main.dart.js 15955:30 Fc.$1 main.dart.js 39208:29 CC.$0 main.dart.js 39182:9 r2.n2 main.dart.js 39205:12 CD.$1 main.dart.js 39208:29 CC.$0 ===== asynchronous gap =========================== ```