Update charted to 0.4.8 and roll

packages/unittest/lib/src/matcher/util.dart

Index: packages/unittest/lib/src/matcher/util.dart
diff --git a/packages/unittest/lib/src/matcher/util.dart b/packages/unittest/lib/src/matcher/util.dart
index b98c1a84af8ac8106bae34571f41e1b4bc5fd251..1550974d05b62e6b4d48d4ea9ba0daba32804e93 100644
--- a/packages/unittest/lib/src/matcher/util.dart
+++ b/packages/unittest/lib/src/matcher/util.dart
@@ -7,6 +7,8 @@ library unittest.matcher.util;
 import 'core_matchers.dart';
 import 'interfaces.dart';
 
+typedef bool _Predicate(value);
+
 /// A [Map] between whitespace characters and their escape sequences.
 const _escapeMap = const {
   '\n': r'\n',
@@ -38,7 +40,7 @@ void addStateInfo(Map matchState, Map values) {
 Matcher wrapMatcher(x) {
   if (x is Matcher) {
     return x;
-  } else if (x is Function) {
+  } else if (x is _Predicate) {
     return predicate(x);
   } else {
     return equals(x);