Unbreak pub:

tools/dom/templates/immutable_list_mixin.darttemplate

Index: tools/dom/templates/immutable_list_mixin.darttemplate
diff --git a/tools/dom/templates/immutable_list_mixin.darttemplate b/tools/dom/templates/immutable_list_mixin.darttemplate
index 850c2f82ab3a785cfedf13e1b84796ab0f3a5c85..2c8bf6814002a5c80e31a1382cc1670dcb55f2ca 100644
--- a/tools/dom/templates/immutable_list_mixin.darttemplate
+++ b/tools/dom/templates/immutable_list_mixin.darttemplate
@@ -32,6 +32,9 @@ $endif
   Iterable map(f($E element)) =>
       IterableMixinWorkaround.mapList(this, f);
 
+  List mappedBy(f($E element)) =>
+      IterableMixinWorkaround.mappedByList(this, f);
+
   Iterable<$E> where(bool f($E element)) =>
       IterableMixinWorkaround.where(this, f);
 
@@ -104,7 +107,7 @@ $else
   // clear() defined by IDL.
 $endif
 
-  Iterable<$E> get reversed {
+  List<$E> get reversed {
     return IterableMixinWorkaround.reversedList(this);
   }