Merge pull request #17628 from jonnyynnoj/master

[mainloop.js] UMD format

types/mainloop.js/index.d.ts

@@ -26,3 +26,6 @@ interface MainLoop {
 }
 
 declare var MainLoop: MainLoop;
+
+export = MainLoop;
+export as namespace MainLoop;

types/mainloop.js/tsconfig.json

@@ -20,4 +20,4 @@
         "index.d.ts",
         "mainloop.js-tests.ts"
     ]
-}
+}