Fix tranced es5 classes after new scope

src/services/navigationBar.ts

@@ -163,6 +163,7 @@ namespace ts.NavigationBar {
         // Save the old parent
         parentsStack.push(parent);
         trackedEs5ClassesStack.push(trackedEs5Classes);
+        trackedEs5Classes = undefined;
         parent = navNode;
     }
 

tests/cases/fourslash/navigationBarWithLocalVariables.ts

@@ -0,0 +1,23 @@
+/// <reference path="fourslash.ts"/>
+
+//// function x(){
+//// 	const x = Object()
+//// 	x.foo = ""
+//// }
+
+verify.navigationTree({
+    "text": "<global>",
+    "kind": "script",
+    "childItems": [
+        {
+            "text": "x",
+            "kind": "function",
+            "childItems": [
+                {
+                    "text": "x",
+                    "kind": "const"
+                }
+            ]
+        }
+    ]
+});