Fixing test to check the new realist implementation of dynamic cast

Author: Robertorosmaninho

test/Interop/SwiftToCxx/functions/swift-functions-errors-execution.cpp

@@ -28,10 +28,8 @@ int main() {
     Functions::throwFunction();
   } catch (swift::Error& e) {
       auto errorVal = e.as<Functions::NaiveErrors>();
-      if (errorVal) {
-        assert(errorVal == Functions::NaiveErrors::throwError);
-        errorVal->getMessage();
-      }
+      assert(errorVal == Functions::NaiveErrors::throwError);
+      errorVal.getMessage();
   }
   try {
     Functions::throwFunctionWithReturn();
@@ -50,4 +48,4 @@ int main() {
 // CHECK-NEXT: throwError
 // CHECK-NEXT: passThrowFunctionWithReturn
 // CHECK-NEXT: Exception
-// CHECK-NEXT: Test destroyed
+// CHECK-NEXT: Test destroyed