Make `this` available in closures if a type variable is used as expression.

tests/language/language.status

 # Copyright (c) 2012, 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.
 
 # This directory contains tests that are intended to show the
 # current state of the language.
 
 # In order to maintain maximum test coverage for all builds,
 # please use the following procedure to mark a test
 # failed on architectures other than the one you are working on.
 #
 # 1) Copy the old version of the test to
 #    tests/language/src/test_name_[dartc|vm]_test.dart.
 #    to maintain coverage.
 # 2) File a bug on each architecture for the failure due to the language change.
 # 3) Update the language/src directory with the updated test.
 
+[ $compiler == dart2dart ]
+closure_type_variable_test: Fail # Type variable used as expression (dartbug.com/6282)
+
 [ $compiler == none ]
+closure_type_variable_test: Fail # Type variable used as expression (dartbug.com/6282)
 built_in_identifier_prefix_test: Fail # http://dartbug.com/6970
 library_juxtaposition_test: Fail # Issue 6877
 gc_test: Pass, Fail # Issue 1487
 pseudo_kw_illegal_test/14: Fail  # Issue 356
 method_override2_test/00: Fail # Issue 7076.
 method_override2_test/02: Fail # Issue 7076.
 method_override2_test/03: Fail # Issue 7076.
 
 # These bugs refer currently ongoing language discussions.
 constructor5_test: Fail           # (Discussion ongoing)
@@ skipping 531 matching lines @@
 *: Skip
 
 [ $arch == simarm ]
 *: Skip
 
 [ $arch == mips ]
 *: Skip
 
 [ $arch == simmips ]
 *: Skip