Support type variables as expressions.

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.
@@ skipping 358 matching lines @@
 prefix16_test: Fail
 prefix22_test: Fail
 type_annotation_test/04: Fail
 type_annotation_test/06: Fail
 
 # Calling unresolved class constructor:
 call_nonexistent_constructor_test: Fail
 
 bad_override_test/01: Fail
 bad_override_test/02: Fail
-illegal_invocation_test/01: Fail, OK # Typedef literals are expressions now.
-illegal_invocation_test/04: Fail, OK # Class literals are expressions now.
-illegal_invocation_test/05: Fail, OK # Type variables are expressions now.
 
 first_class_types_constants_test: Fail # Issue 6282
 
 # Missing compile-time error when modifying final local variables
 final_variable_assignment_test/01: Fail
 final_variable_assignment_test/02: Fail
 final_variable_assignment_test/03: Fail
 final_variable_assignment_test/04: Fail
 
 compile_time_constant10_test/01: Fail # http://dartbug.com/5519
@@ skipping 15 matching lines @@
 const_syntax_test/10: Fail # http://dartbug.com/5519
 constructor_named_arguments_test/01: Fail # http://dartbug.com/5519
 final_for_in_variable_test/01: Fail # http://dartbug.com/5519
 final_is_not_const_test/01: Fail # http://dartbug.com/5519
 final_syntax_test/01: Fail # http://dartbug.com/5519
 final_syntax_test/02: Fail # http://dartbug.com/5519
 final_syntax_test/03: Fail # http://dartbug.com/5519
 final_syntax_test/04: Fail # http://dartbug.com/5519
 getter_no_setter_test/01: Fail # http://dartbug.com/5519
 getter_no_setter2_test/01: Fail # http://dartbug.com/5519
-illegal_invocation_test/03: Fail # http://dartbug.com/5519
 isnot_malformed_type_test/01: Fail # http://dartbug.com/5519
 method_override2_test/01: Fail # http://dartbug.com/5519
 named_parameters_aggregated_test/01: Fail # http://dartbug.com/5519
 named_parameters_aggregated_test/03: Fail # http://dartbug.com/5519
 not_enough_positional_arguments_test/01: Fail # http://dartbug.com/5519
 
 throw_expr_test: Fail
 metadata_test: Fail
 # Fails in conservative mode, issue 4935, passes in minifinying mode.
 bad_constructor_test/04: Fail
@@ skipping 135 matching lines @@
 *: Skip
 
 [ $arch == simarm ]
 *: Skip
 
 [ $arch == mips ]
 *: Skip
 
 [ $arch == simmips ]
 *: Skip