From 5cc1895797c78fee98f72f47c03ccbae1ddb9f2b Mon Sep 17 00:00:00 2001
From: Jonas Jenwald <jonas.jenwald@gmail.com>
Date: Mon, 20 Aug 2018 12:14:37 +0200
Subject: [PATCH] Add a `Symbol` polyfill, using core-js, to allow using
 `for...of` loops

https://github.com/zloirock/core-js#ecmascript-symbol
---
 src/shared/compatibility.js | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/src/shared/compatibility.js b/src/shared/compatibility.js
index 6855c2faa16ae2..a44afbbdb5f88b 100644
--- a/src/shared/compatibility.js
+++ b/src/shared/compatibility.js
@@ -165,6 +165,14 @@ const hasDOM = typeof window === 'object' && typeof document === 'object';
   globalScope.WeakMap = require('core-js/fn/weak-map');
 })();
 
+// Support: IE
+(function checkSymbol() {
+  if (globalScope.Symbol) {
+    return;
+  }
+  require('core-js/es6/symbol');
+})();
+
 } // End of !PDFJSDev.test('CHROME')
 
 // Provides support for Object.values in legacy browsers.