Use .packages instead of pubspec.yaml

pkg/dev_compiler/lib/src/compiler/nullable_type_inference.dart

Index: pkg/dev_compiler/lib/src/compiler/nullable_type_inference.dart
diff --git a/pkg/dev_compiler/lib/src/compiler/nullable_type_inference.dart b/pkg/dev_compiler/lib/src/compiler/nullable_type_inference.dart
index e1821e0fc8b51714b91ce512dff3169399900f4a..39f01308324edbb22a8b5d05d18574e643c087d4 100644
--- a/pkg/dev_compiler/lib/src/compiler/nullable_type_inference.dart
+++ b/pkg/dev_compiler/lib/src/compiler/nullable_type_inference.dart
@@ -235,6 +235,7 @@ class _NullableLocalInference extends RecursiveAstVisitor {
       // they are nullable too.
       _assignments.remove(e)?.forEach(visitNullableLocal);
     }
+
     _nullableLocals.forEach(visitNullableLocal);
 
     // Any remaining locals are non-null.