Move browser related objects from global to function level (michalsni…

…k#349)

src/js/aos.js

@@ -23,10 +23,6 @@ import elements from './helpers/elements';
 let $aosElements = [];
 let initialized = false;
 
-// Detect not supported browsers (<=IE9)
-// http://browserhacks.com/#hack-e71d8692f65334173fee715c222cb805
-const browserNotSupported = document.all && !window.atob;
-
 /**
  * Default options
  */
@@ -130,6 +126,10 @@ const init = function init(settings) {
   // Create initial array with elements -> to be fullfilled later with prepare()
   $aosElements = elements();
 
+  // Detect not supported browsers (<=IE9)
+  // http://browserhacks.com/#hack-e71d8692f65334173fee715c222cb805
+  const browserNotSupported = document.all && !window.atob;
+
   /**
    * Don't init plugin if option `disable` is set
    * or when browser is not supported

src/js/libs/observer.js

@@ -1,12 +1,12 @@
-const doc = window.document;
-const MutationObserver =
+let callback = () => {};
+
+function ready(selector, fn) {
+  const doc = window.document;
+  const MutationObserver =
   window.MutationObserver ||
   window.WebKitMutationObserver ||
   window.MozMutationObserver;
 
-let callback = () => {};
-
-function ready(selector, fn) {
   const observer = new MutationObserver(check);
   callback = fn;