Add preliminary parser support for generic function types

tests/language/language_analyzer2.status

Index: tests/language/language_analyzer2.status
diff --git a/tests/language/language_analyzer2.status b/tests/language/language_analyzer2.status
index bb122105bcdaa0300203d88b983dd4954e8c921c..7d87bb16a3ec901146ec937d87b11fa8a30926fb 100644
--- a/tests/language/language_analyzer2.status
+++ b/tests/language/language_analyzer2.status
@@ -14,6 +14,9 @@ covariant_override_test: CompileTimeError # Issue 28167
 # Runtime negative test. No static errors or warnings.
 closure_call_wrong_argument_count_negative_test: skip
 
+# No longer support the old use of typedef to define a mixin
+mixin_illegal_syntax_test/00: Crash
+
 deep_nesting1_negative_test: Crash # Issue 25558
 deep_nesting2_negative_test: Crash # Issue 25558