add test for non-transient symbol

tests/cases/fourslash/refactorConvertToNamedParameters_methodCallUnion.ts

@@ -0,0 +1,29 @@
+/// <reference path='fourslash.ts' />
+
+////class A {
+////    /*a*/foo/*b*/(a: number, b: number) { return a + b; }
+////}
+////class B {
+////    foo(c: number, d: number) { return c + d; }
+////}
+////function foo(ab: A | B) {
+////    return ab.foo(1, 2);
+////}
+
+
+goTo.select("a", "b");
+// Refactor should not make changes
+edit.applyRefactor({
+    refactorName: "Convert to named parameters",
+    actionName: "Convert to named parameters",
+    actionDescription: "Convert to named parameters",
+    newContent: `class A {
+    foo(a: number, b: number) { return a + b; }
+}
+class B {
+    foo(c: number, d: number) { return c + d; }
+}
+function foo(ab: A | B) {
+    return ab.foo(1, 2);
+}`
+});