Adding regression test

ahejlsberg · ahejlsberg · commit cd88f1ea323f · 2016-04-12T13:40:21.000-07:00
diff --git a/tests/cases/conformance/controlFlow/controlFlowWhileStatement.ts b/tests/cases/conformance/controlFlow/controlFlowWhileStatement.ts
@@ -37,7 +37,9 @@ function e() {
     let x: string | number;
     x = "";
     while (cond) {
+        x; // string | number
         x = 42;
+        x; // number
     }
     x; // string | number
 }
