Fix Set.from which still had a generic type on the incoming Iterable.

sdk/lib/collection/linked_hash_set.dart

Index: sdk/lib/collection/linked_hash_set.dart
diff --git a/sdk/lib/collection/linked_hash_set.dart b/sdk/lib/collection/linked_hash_set.dart
index a4848f46693759f5d9c803d5e157d5b8d0c564ca..19d2fefcbdeb4224674ff7869b8b725b20c8c3f4 100644
--- a/sdk/lib/collection/linked_hash_set.dart
+++ b/sdk/lib/collection/linked_hash_set.dart
@@ -102,7 +102,7 @@ abstract class LinkedHashSet<E> implements HashSet<E> {
    *     Iterable<SuperType> tmp = superSet.where((e) => e is SubType);
    *     Set<SubType> subSet = new LinkedHashSet<SubType>.from(tmp);
    */
-  factory LinkedHashSet.from(Iterable<E> elements) {
+  factory LinkedHashSet.from(Iterable elements) {
     LinkedHashSet<E> result = new LinkedHashSet<E>();
     for (final E element in elements) {
       result.add(element);