Dart SDK Spelling b, c, and d.

tests/lib/mirrors/mirrors_used_typedef_declaration_test.dart

 // Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library test;
 
 import 'package:expect/expect.dart';
 
 @MirrorsUsed(targets: "Foo")
 import 'dart:mirrors';
 
 typedef int Foo(String x);
 typedef int Bar();
 
 main() {
   LibraryMirror thisLibrary = currentMirrorSystem().findLibrary(#test);
 
   Mirror fooMirror = thisLibrary.declarations[#Foo];
 
   Expect.isTrue(fooMirror != null, 'Foo not found.');
   Expect.isTrue(thisLibrary.declarations[#Foo] is TypedefMirror,
       'TypedefMirror expected, found $fooMirror');
 
-  // The following code does not currenty work on the VM, because it does not
+  // The following code does not currently work on the VM, because it does not
   // support MirrorsUsed (see dartbug.com/16048).
   Mirror barMirror = thisLibrary.declarations[#Bar]; //             //# 01: ok
   Expect.isTrue(barMirror == null, //                               //# 01: continued
                 'Bar should not be emitted due to MirrorsUsed.'); //# 01: continued
 }