Rename mappedBy to map.

sdk/lib/collection/collections.dart

Index: sdk/lib/collection/collections.dart
diff --git a/sdk/lib/collection/collections.dart b/sdk/lib/collection/collections.dart
index f9e83eed8318f1e96d11b4265bf21b888b88a9e6..0c45e21d4250f85f4e04110279d4fb89403f8e76 100644
--- a/sdk/lib/collection/collections.dart
+++ b/sdk/lib/collection/collections.dart
@@ -313,12 +313,18 @@ class IterableMixinWorkaround {
     return new WhereIterable(iterable, f);
   }
 
+  static Iterable map(Iterable iterable, f(var element)) {
+    return new MappedIterable(iterable, f);
+  }
+
   static List mappedByList(List list, f(var element)) {
+    // This is currently a List as well as an Iterable.
     return new MappedList(list, f);
   }
 
-  static List takeList(List list, int n) {
+  static Iterable takeList(List list, int n) {
     // The generic type is currently lost. It will be fixed with mixins.
+    // This is currently a List as well as an Iterable.
     return new ListView(list, 0, n);
   }
 
@@ -327,8 +333,9 @@ class IterableMixinWorkaround {
     return new TakeWhileIterable(iterable, test);
   }
 
-  static List skipList(List list, int n) {
+  static Iterable skipList(List list, int n) {
     // The generic type is currently lost. It will be fixed with mixins.
+    // This is currently a List as well as an Iterable.
     return new ListView(list, n, null);
   }
 
@@ -443,7 +450,7 @@ class Collections {
       => IterableMixinWorkaround.mappedByList(list, f);
 
   /** Deprecated. Use the same method in [IterableMixinWorkaround] instead.*/
-  static List takeList(List list, int n)
+  static Iterable takeList(List list, int n)
       => IterableMixinWorkaround.takeList(list, n);
 
   /** Deprecated. Use the same method in [IterableMixinWorkaround] instead.*/
@@ -451,7 +458,7 @@ class Collections {
       => IterableMixinWorkaround.takeWhile(iterable, test);
 
   /** Deprecated. Use the same method in [IterableMixinWorkaround] instead.*/
-  static List skipList(List list, int n)
+  static Iterable skipList(List list, int n)
       => IterableMixinWorkaround.skipList(list, n);
 
   /** Deprecated. Use the same method in [IterableMixinWorkaround] instead.*/