[jquery] Fix issue with resolving Symbol when used with ES5.

types/jquery/index.d.ts

@@ -5855,10 +5855,23 @@ interface JQuery<TElement = HTMLElement> extends Iterable<TElement> {
     [n: number]: TElement;
 }
 
-// ES5 compatibility
+// #region ES5 compatibility
+
 // tslint:disable-next-line:no-empty-interface
 interface Iterable<T> { }
 
+interface SymbolConstructor {
+    /**
+     * A String value that is used in the creation of the default string description of an object.
+     * Called by the built-in method Object.prototype.toString.
+     */
+    readonly toStringTag: symbol;
+}
+
+declare var Symbol: SymbolConstructor;
+
+// #endregion
+
 declare namespace JQuery {
     type TypeOrArray<T> = T | T[];
     type Node = Element | Text | Comment | DocumentFragment;