Dynamic -> dynamic.

sdk/lib/core/collection.dart

Index: sdk/lib/core/collection.dart
diff --git a/sdk/lib/core/collection.dart b/sdk/lib/core/collection.dart
index 51ffc39761c0ec4c42702eb6f6c8db62ef0abe26..2565c48f1e05b2bb93e0bda3e5f936d3b1e3d14e 100644
--- a/sdk/lib/core/collection.dart
+++ b/sdk/lib/core/collection.dart
@@ -63,8 +63,8 @@ abstract class Collection<E> extends Iterable<E> {
    *
    *   collection.reduce(0, (prev, element) => prev + element);
    */
-  Dynamic reduce(var initialValue,
-                 Dynamic combine(var previousValue, E element)) {
+  dynamic reduce(var initialValue,
+                 dynamic combine(var previousValue, E element)) {
     var value = initialValue;
     for (E element in this) value = combine(value, element);
     return value;