Add more mixin tests and start rejecting illegal syntax.

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 42 matching lines @@
 type_annotation_test/04: Fail # Issue 6970
 type_annotation_test/06: Fail # Issue 6973
 type_annotation_test/09: Fail # Issue 6973
 
 type_parameter_literal_test: Fail # Issue 7551
 
 mixin_field_test: Fail
 mixin_is_test: Fail
 mixin_method_test: Fail
 mixin_naming_test: Fail
-
 mixin_extends_field_test: Fail
 mixin_extends_is_test: Fail
 mixin_extends_method_test: Fail
+mixin_mixin_test: Fail
+mixin_illegal_syntax_test/none: Fail
 
 [ $compiler == none && ($system == macos || $system == linux) && $arch == ia32 && $checked ]
 gc_test: Skip  # Issue 1487, flaky.
 
 [ $compiler == none && $mode == debug ]
 gc_test: Skip  # Takes too long.
 
 [ $compiler == none && $unchecked ]
 
 # Only checked mode reports an error on type assignment
@@ skipping 265 matching lines @@
 type_checks_in_factory_method_test: Fail
 default_factory2_test/01: Fail # type arguments on redirecting factory not implemented
 default_factory3_test: Fail # type arguments on redirecting factory not implemented
 non_parameterized_factory_test: Fail # type arguments on redirecting factory not implemented
 non_parameterized_factory2_test: Fail # type arguments on redirecting factory not implemented
 type_variable_scope_test: Fail # type arguments on redirecting factory not implemented
 
 many_overridden_no_such_method_test: Fail, Pass, OK # Fails in minified mode, test depends on method names.
 overridden_no_such_method_test: Fail, Pass, OK # Fails in minified mode, test depends on method names.
 
-# Mixins aren't unparsed the right way yet.
-mixin_field_test: Fail # http://dartbug.com/7972
-mixin_is_test: Fail # http://dartbug.com/7972
-mixin_method_test: Fail # http://dartbug.com/7972
-mixin_naming_test: Fail # http://dartbug.com/7972
-
-mixin_extends_field_test: Fail # http://dartbug.com/7972
-mixin_extends_is_test: Fail # http://dartbug.com/7972
-mixin_extends_method_test: Fail # http://dartbug.com/7972
+# Mixins fail on the VM.
+mixin_field_test: Fail                # VM issue
+mixin_is_test: Fail                   # VM issue
+mixin_method_test: Fail               # VM issue
+mixin_naming_test: Fail               # VM issue
+mixin_extends_field_test: Fail        # VM issue
+mixin_extends_is_test: Fail           # VM issue
+mixin_extends_method_test: Fail       # VM issue
+mixin_mixin_test: Fail                # VM issue
+mixin_illegal_syntax_test/none: Fail  # VM issue
 
 # Malformed types not handled as unresolved:
 import_core_prefix_test: Fail
 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
@@ skipping 175 matching lines @@
 
 [ $compiler == dart2dart && $minified ]
 # TODO(tball): Assign proper bug numbers.
 class_literal_test/none: Fail
 
 import_core_prefix_test: Pass
 prefix22_test: Pass
 invocation_mirror_test: Fail, OK # hardcoded names.
 invocation_mirror2_test: Fail, OK # hardcoded names.
 super_call4_test: Fail, OK # hardcoded names.