reapply TextInput es6 conversion with fixes, attemps to fix

Summary: D10515754 reapplied by backing out D12989604 and then fixed by manually forwarding the instance methods to the host function instead of using `forwardRef`. This also removes the need for the $flowFixMe.

Reviewed By: TheSavior

Differential Revision: D13048482

fbshipit-source-id: ff2447aff123e0960eddaef645f7dc976a426e14

Libraries/Components/TextInput/__tests__/TextInput-test.js

@@ -12,12 +12,11 @@
 'use strict';
 
 const React = require('React');
-const ReactTestRenderer = require('react-test-renderer');
 const TextInput = require('TextInput');
 
 import Component from '@reactions/component';
 
-const {enter} = require('ReactNativeTestTools');
+const {enter, renderWithStrictMode} = require('ReactNativeTestTools');
 
 jest.unmock('TextInput');
 
@@ -29,7 +28,7 @@ describe('TextInput tests', () => {
   beforeEach(() => {
     onChangeListener = jest.fn();
     onChangeTextListener = jest.fn();
-    const renderTree = ReactTestRenderer.create(
+    const renderTree = renderWithStrictMode(
       <Component initialState={{text: initialValue}}>
         {({setState, state}) => (
           <TextInput