feat(web/RN): update React to v16 and React Native to 0.49

react/features/unsupported-browser/components/HideNotificationBarStyle.js

@@ -9,7 +9,7 @@ import React, { Component } from 'react';
  * @private
  * @returns {ReactElement}
  */
-export default class HideNotificationBarStyles extends Component {
+export default class HideNotificationBarStyles extends Component<*> {
 
     /**
      * Implements React's {@link Component#render()}.

react/features/unsupported-browser/components/NoMobileApp.js

@@ -11,7 +11,7 @@ declare var interfaceConfig: Object;
  *
  * @class NoMobileApp
  */
-export default class NoMobileApp extends Component {
+export default class NoMobileApp extends Component<*> {
     /**
      * Renders the component.
      *

react/features/unsupported-browser/components/PluginRequiredBrowser.js

@@ -9,7 +9,7 @@ import { CHROME, CHROMIUM, FIREFOX } from './browserLinks';
  *
  * @class PluginRequiredBrowser
  */
-export default class PluginRequiredBrowser extends Component {
+export default class PluginRequiredBrowser extends Component<*> {
 
     /**
      * Renders the component.

react/features/unsupported-browser/components/UnsupportedDesktopBrowser.js

@@ -22,7 +22,7 @@ const _SNS = 'unsupported-desktop-browser';
  *
  * @class UnsupportedDesktopBrowser
  */
-class UnsupportedDesktopBrowser extends Component {
+class UnsupportedDesktopBrowser extends Component<*> {
     /**
      * UnsupportedDesktopBrowser component's property types.
      *

react/features/unsupported-browser/components/UnsupportedMobileBrowser.js

@@ -42,7 +42,7 @@ const _URLS = {
  *
  * @class UnsupportedMobileBrowser
  */
-class UnsupportedMobileBrowser extends Component {
+class UnsupportedMobileBrowser extends Component<*, *> {
     state: Object;
 
     /**