Implement is-checks against type variables.

tests/language/language_dart2js.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.
 
 [ $compiler == dart2js || $compiler == dart2dart ]
 class_literal_test/01: Fail # Class literals are expression now; delete this test.
 class_literal_test/02: Fail # Class literals are expression now; delete this test.
 class_literal_test/05: Fail # Class literals are expression now; delete this test.
 class_literal_test/06: Fail # Class literals are expression now; delete this test.
 class_literal_test/07: Fail # Class literals are expression now; delete this test.
@@ skipping 14 matching lines @@
 class_literal_test/26: Fail # Class literals are expression now; delete this test.
 class_literal_test/27: Fail # Class literals are expression now; delete this test.
 class_literal_test/28: Fail # Class literals are expression now; delete this test.
 class_literal_test/29: Fail # Class literals are expression now; delete this test.
 
 # VM specific tests that should not be run by dart2js.
 *vm_test: Skip
 *vm_negative_test: Skip
 
 [ $compiler == dart2js && $checked ]
+mixin_type_parameters_super_extends_test: Fail # http://dartbug.com/8116
+mixin_type_parameters_super_test: Fail # http://dartbug.com/8116
 prefix16_test: Fail # dartbug.com/7354
 default_factory2_test/01: Pass # For the wrong reasons.
 type_variable_scope_test/none: Fail
 factory_implementation_test/00: Fail
 redirecting_factory_infinite_steps_test/01: Fail
 type_variable_bounds_test/01: Fail
 type_variable_bounds_test/02: Fail
 type_variable_bounds_test/04: Fail
 type_variable_bounds_test/05: Fail
 type_variable_bounds2_test/00: Fail
@@ skipping 150 matching lines @@
 named_parameters_aggregated_test/05: Fail # Absence of positional parameters before named parameters does not trigger static type warning.
 pseudo_kw_test: Fail # Unexpected token '('
 super_implicit_closure_test: Fail # internal error: super property read not implemented
 super_operator_test: Fail # internal error: super property store not implemented
 switch_label_test: Fail # error: target of continue is not a loop or switch case
 on_catch_malformed_type_test: Fail # Malformed types cause compile-time errors.
 
 
 # Failing tests for mixin type parameters.
 mixin_type_parameters_mixin_test: Fail # http://dartbug.com/8116
-mixin_type_parameters_super_test: Fail # http://dartbug.com/8116
 mixin_type_parameters_mixin_extends_test: Fail # http://dartbug.com/8116
-mixin_type_parameters_super_extends_test: Fail # http://dartbug.com/8116
 
 
 # External tests.
 external_test/01: Fail
 external_test/02: Fail
 external_test/11: Fail
 external_test/12: Fail
 external_test/13: Skip  # Runtime error (missing patch).
 external_test/14: Fail
 external_test/15: Fail
@@ skipping 147 matching lines @@
 call_through_null_getter_test: Fail
 closure3_test: Fail
 execute_finally3_test: Fail
 method_invocation_test: Fail
 null_pointer_exception_test: Fail
 stack_overflow_test: Fail
 stack_overflow_stacktrace_test: Fail
 string_interpolate_npe_test: Fail
 closure_call_wrong_argument_count_negative_test: Skip
 label_test: Skip