Fix class inheritance in IE10 (#7969)

* Revert "Move subclass inheritance to end (#7772)"

This reverts commit f8ab9466d3.

* Only use getPrototypeOf if setPrototypeOf is implemented

* Update fixtures

* Helpers updates

* Update fixtures

* Fall back to getPrototypeOf

* Update fixtures

packages/babel-plugin-transform-classes/test/fixtures/spec/super-reference-before-in-lambda/output.js

@@ -3,6 +3,8 @@ var Foo =
 function (_Bar) {
   "use strict";
 
+  babelHelpers.inherits(Foo, _Bar);
+
   function Foo() {
     var _this;
 
@@ -13,6 +15,5 @@ function (_Bar) {
     return _this = babelHelpers.possibleConstructorReturn(this, babelHelpers.getPrototypeOf(Foo).call(this));
   }
 
-  babelHelpers.inherits(Foo, _Bar);
   return Foo;
 }(Bar);