Format all dart: library files

sdk/lib/core/expando.dart

Index: sdk/lib/core/expando.dart
diff --git a/sdk/lib/core/expando.dart b/sdk/lib/core/expando.dart
index 1e8a47a2b7d9ec7faa761faf118abb632972c8c1..92cf90c8b2bafe733a2698e2533526a0c64c9535 100644
--- a/sdk/lib/core/expando.dart
+++ b/sdk/lib/core/expando.dart
@@ -23,7 +23,6 @@ part of dart.core;
  * since they will stay alive forever.
  */
 class Expando<T> {
-
   /**
    * The name of the this [Expando] as passed to the constructor. If
    * no name was passed to the constructor, the name is [:null:].
@@ -60,5 +59,4 @@ class Expando<T> {
    * The object must not be a number, a string, a boolean or null.
    */
   external void operator []=(Object object, T value);
-
 }