AST: Remove no longer necessary checks of getSuperclassForDecl() result

Author: slavapestov

lib/AST/ConformanceLookupTable.cpp

@@ -862,8 +862,6 @@ DeclContext *ConformanceLookupTable::getConformingContext(
       Type classTy = nominal->getDeclaredInterfaceType();
       do {
         Type superclassTy = classTy->getSuperclassForDecl(superclassDecl);
-        if (superclassTy->is<ErrorType>())
-          return nullptr;
         auto inheritedConformance = swift::lookupConformance(
             superclassTy, protocol, /*allowMissing=*/false);
         if (inheritedConformance)
@@ -936,8 +934,6 @@ ConformanceLookupTable::getConformance(NominalTypeDecl *nominal,
     // declared.
     auto *conformingClass = cast<ClassDecl>(conformingNominal);
     Type superclassTy = type->getSuperclassForDecl(conformingClass);
-    if (superclassTy->is<ErrorType>())
-      return nullptr;
 
     // Look up the inherited conformance.
     auto inheritedConformance = swift::lookupConformance(

lib/Sema/TypeCheckStorage.cpp

@@ -1146,12 +1146,7 @@ static Expr *buildStorageReference(AccessorDecl *accessor,
       auto *baseClass = override->getDeclContext()->getSelfClassDecl();
       selfTypeForAccess = selfTypeForAccess->getSuperclassForDecl(baseClass);
 
-      // Error recovery path. We get an ErrorType here if getSuperclassForDecl()
-      // fails (because, for instance, a generic parameter of a generic nominal
-      // type cannot be resolved).
-      if (!selfTypeForAccess->is<ErrorType>()) {
-        subs = selfTypeForAccess->getContextSubstitutionMap(baseClass);
-      }
+      subs = selfTypeForAccess->getContextSubstitutionMap(baseClass);
 
       storage = override;