Handle for-in loops

test/dart_codegen/expect/collection/hash_set.dart

Index: test/dart_codegen/expect/collection/hash_set.dart
diff --git a/test/dart_codegen/expect/collection/hash_set.dart b/test/dart_codegen/expect/collection/hash_set.dart
index 77031a8511ee9ff74cc0d86ca3288748f493c0f9..b9e9b03f29121836472364ba225213ebd969195f 100644
--- a/test/dart_codegen/expect/collection/hash_set.dart
+++ b/test/dart_codegen/expect/collection/hash_set.dart
@@ -2,14 +2,14 @@ part of dart.collection;
  abstract class _HashSetBase<E> extends SetBase<E> {Set<E> difference(Set<Object> other) {
   Set<E> result = _newSet();
    for (var element in this) {
-    if (!other.contains(element)) result.add(DEVC$RT.cast(element, dynamic, E, "CompositeCast", """line 17, column 48 of dart:collection/hash_set.dart: """, element is E, false));
+    if (!other.contains(element)) result.add(element);
     }
    return result;
   }
  Set<E> intersection(Set<Object> other) {
   Set<E> result = _newSet();
    for (var element in this) {
-    if (other.contains(element)) result.add(DEVC$RT.cast(element, dynamic, E, "CompositeCast", """line 25, column 47 of dart:collection/hash_set.dart: """, element is E, false));
+    if (other.contains(element)) result.add(element);
     }
    return result;
   }
@@ -22,7 +22,11 @@ bool equals(E e1, E e2), int hashCode(E e), bool isValidKey(potentialKey)}
  external factory HashSet.identity();
  factory HashSet.from(Iterable elements) {
 HashSet<E> result = new HashSet<E>();
- for (E e in elements) result.add(e);
+ for (E e in DEVC$RT.cast(elements, DEVC$RT.type((Iterable<dynamic> _) {
+  }
+), DEVC$RT.type((Iterable<E> _) {
+  }
+), "CompositeCast", """line 103, column 17 of dart:collection/hash_set.dart: """, elements is Iterable<E>, false)) result.add(e);
  return result;
 }
  Iterator<E> get iterator;