Move tests using frog 'native' extension from tests/language to frog/tests

frog/gen.dart

 // Copyright (c) 2011, 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.
 
 /**
  * Top level generator object for writing code and keeping track of
  * dependencies.
  *
  * Should have two compilation models, but only one implemented so far.
  *
@@ skipping 259 matching lines @@
     var typeName = type.jsname != null ? type.jsname : 'top level';
     writer.comment('// ********** Code for ${typeName} **************');
     if (type.isNative && !type.isTop) {
       var nativeName = type.definition.nativeType.name;
       if (nativeName == '') {
         writer.writeln('function ${type.jsname}() {}');
       } else if (type.jsname != nativeName) {
         if (type.isHiddenNativeType) {
           // This is a holder for static methods.
           // TODO(sra): Generate only if used.
-          writer.writeln('function ${type.jsname}() {}');
+          writer.writeln('var ${type.jsname} = {};');
         } else {
           writer.writeln('${type.jsname} = ${nativeName};');
         }
       }
     }
 
     // We need the $inherits function to be declared before factory constructors
     // so that inheritance ($inherits) will work correctly in IE.
     if (!type.isTop) {
       if (type is ConcreteType) {
@@ skipping 2260 matching lines @@
       result.add(new Value(world.varType, '\$$i', null, /*needsTemp:*/false));
     }
     for (int i = bareCount; i < length; i++) {
       var name = getName(i);
       if (name == null) name = '\$$i';
       result.add(new Value(world.varType, name, null, /*needsTemp:*/false));
     }
     return new Arguments(nodes, result);
   }
 }