Dart SDK Spelling b, c, and d.

tests/compiler/dart2js/async_await_js_transform_test.dart

 // Copyright (c) 2015, 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.
 
 import "package:expect/expect.dart";
 import "package:compiler/src/js/js.dart";
 import "package:compiler/src/js/rewrite_async.dart";
 import "package:compiler/src/js_backend/js_backend.dart" show StringBackedName;
 
 void testTransform(String source, String expected, AsyncRewriterBase rewriter) {
@@ skipping 964 matching lines @@
         return y;
       case await bar(): // await in case
         print(await foobar(x));
         return y;
       case x:
         if (a) {
           throw new Error();
         } else {
           continue;
         }
-      default: // defaul case
+      default: // default case
         break lab; // break to label
       }
       foo();
     }
   }
 }""",
       """
 function(x, y, k) {
   var __goto = 0, __completer = new Completer(), __returnValue, __handler = 2, __currentError, __temp1;
   var body = _wrapJsFunctionForAsync(function(__errorCode, __result) {
@@ skipping 269 matching lines @@
             // return
             return endOfIteration();
           case 2:
             // rethrow
             return uncaughtError(__currentError);
         }
     };
   });
 }""");
 }