Hack around issue with is checks against type variables.

tests/co19/co19-leg.status

Index: tests/co19/co19-leg.status
diff --git a/tests/co19/co19-leg.status b/tests/co19/co19-leg.status
index 966b27a06c394b5fe96a3a35a1f1aaf436dd3ad9..6a040dd48c7f37cd49d73d4f4817b78fd4f6d74d 100644
--- a/tests/co19/co19-leg.status
+++ b/tests/co19/co19-leg.status
@@ -136,14 +136,10 @@ Language/07_Classes/5_Constructors/2_Factories_A01_t01: Fail # compiler cancelle
 Language/07_Classes/8_Superclasses/1_Inheritance_and_Overriding_A02_t03: Fail # compiler cancelled: internal error: super property store not implemented
 Language/08_Interfaces/4_Superinterfaces/1_Inheritance_and_Overriding_A01_t02: Fail # compiler cancelled: no method named foo in class I
 Language/09_Generics/09_Generics_A04_t03: Fail # compiler cancelled: cannot resolve type N
-Language/09_Generics/09_Generics_A04_t04: Fail # compiler cancelled: cannot resolve type T
 Language/11_Statements/13_Continue_A02_t12: Fail # compiler cancelled: cannot resolve label L
 Language/11_Statements/13_Continue_A02_t13: Fail # compiler cancelled: cannot resolve label L
 Language/13_Types/2_Dynamic_Type_System_A02_t01: Fail # compiler cancelled: cannot resolve type MalformedType
-Language/13_Types/4_Interface_Types_A05_t04: Fail # compiler cancelled: cannot resolve type T
-Language/13_Types/4_Interface_Types_A08_t01: Fail # compiler cancelled: cannot resolve type S
 Language/13_Types/5_Function_Types_A02_t01: Fail # compiler cancelled: unexpected token 'call'
-Language/13_Types/6_Type_Dynamic_A02_t01: Fail # compiler cancelled: cannot resolve type S
 Language/13_Types/3_Type_Declarations/1_Typedef_A06_t01: Pass # internal error: visitIs for typedefs not implemented
 Language/13_Types/3_Type_Declarations/1_Typedef_A06_t02: Pass # internal error: visitIs for typedefs not implemented
 Language/13_Types/3_Type_Declarations/1_Typedef_A06_t03: Pass # internal error: visitIs for typedefs not implemented