fixup! fix(change-detector): handle double.NAN for collections (in JS)

Author: mhevery

lib/change_detection/dirty_checking_change_detector.dart

@@ -1027,7 +1027,7 @@ class _CollectionChangeRecord<V> implements CollectionChangeRecord<V> {
         return record..item = item;
       }
 
-      if (item is num && item.isNaN && record.item is num && record.item.isNaN){
+      if (item is num && (item as num).isNaN && record.item is num && (record.item as num).isNaN){
         // we need this for JavaScript since in JS NaN !== NaN.
         return record;
       }

test/change_detection/dirty_checking_change_detector_spec.dart

@@ -735,7 +735,7 @@ abstract class _CollectionMatcher<T> extends Matcher {
   // todo(vicb) merge with _getList() once map is refactored
   List<T> _getCollectionList(Function it) {
     var result = <T>[];
-    it((CollectionChangeItem<V> i) {
+    it((CollectionChangeItem i) {
       result.add(i);
     });
     return result;