Loosen argument type in callback (#65)
The type was technically changed when refactoring to function type
syntax, restore the `dynamic` but make it explicit.
This surfaces as a static problem in the null safety branch. Fix it on
the master branch as well for consistency.
diff --git a/lib/src/chain.dart b/lib/src/chain.dart
index 602b90c..48ac2d9 100644
--- a/lib/src/chain.dart
+++ b/lib/src/chain.dart
@@ -73,7 +73,7 @@
///
/// If [callback] returns a value, it will be returned by [capture] as well.
static T capture<T>(T Function() callback,
- {void Function(Object error, Chain) onError,
+ {void Function(dynamic error, Chain) onError,
bool when = true,
bool errorZone = true}) {
if (!errorZone && onError != null) {
