fix(browser support): make IE lte 10 work by fixing Object.getPrototy…

…peOf

broken since babel6, see https://phabricator.babeljs.io/T3041

src/lib/main.js

@@ -1,5 +1,9 @@
-// required for browsers not supporting this (helper requirement)
+// required for browsers not supporting Object.freeze (helper requirement)
 import '../shams/Object.freeze.js';
+
+// required for IE <= 10 since move to babel6
+import '../shims/Object.getPrototypeOf.js';
+
 import toFactory from 'to-factory';
 import InstantSearch from './InstantSearch.js';
 import algoliasearchHelper from 'algoliasearch-helper';

src/shims/Object.getPrototypeOf.js

@@ -0,0 +1,18 @@
+/* eslint-disable */
+
+// FIX IE <= 10 babel6:
+// - https://phabricator.babeljs.io/T3041
+// - https://phabricator.babeljs.io/T3041#70671
+var testObject = {};
+
+if (!(Object.setPrototypeOf || testObject.__proto__)) {
+  var nativeGetPrototypeOf = Object.getPrototypeOf;
+
+  Object.getPrototypeOf = function(object) {
+    if (object.__proto__) {
+      return object.__proto__;
+    } else {
+      return nativeGetPrototypeOf.call(Object, object);
+    }
+  }
+}