Fix implementation of Function.apply with optional positional arguments.

sdk/lib/_internal/compiler/js_lib/js_helper.dart

 // Copyright (c) 2013, 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 _js_helper;
 
 import 'dart:_async_await_error_codes' as async_error_codes;
 
 import 'dart:_js_embedded_names' show
     DEFERRED_LIBRARY_URIS,
@@ skipping 1163 matching lines @@
       int requiredArgumentCount = info.requiredParameterCount;
       int maxArgumentCount = requiredArgumentCount +
           info.optionalParameterCount;
       if (info.areOptionalParametersNamed ||
           requiredArgumentCount > argumentCount ||
           maxArgumentCount < argumentCount) {
         return functionNoSuchMethod(function, positionalArguments, null);
       }
       arguments = new List.from(arguments);
       for (int pos = argumentCount; pos < maxArgumentCount; pos++) {
-        arguments.add(info.defaultValue(pos));
+        arguments.add(getMetadata(info.defaultValue(pos)));
       }
     }
     // We bound 'this' to [function] because of how we compile
     // closures: escaped local variables are stored and accessed through
     // [function].
     return JS('var', '#.apply(#, #)', jsFunction, function, arguments);
   }
 
   static applyFunctionWithNamedArguments(Function function,
                                          List positionalArguments,
@@ skipping 2708 matching lines @@
   // This is a function that will return a helper function that does the
   // iteration of the sync*.
   //
   // Each invocation should give a body with fresh state.
   final dynamic /* js function */ _outerHelper;
 
   SyncStarIterable(this._outerHelper);
 
   Iterator get iterator => new SyncStarIterator(JS('', '#()', _outerHelper));
 }