Back out "[flipper] Export init function"

Summary:
This seems to break initialization. I'm not quite sure why, but
inside the exported function, nothing else from the file appears
to be visible.

Original commit changeset: 55b2a61186e6

Reviewed By: danielbuechele

Differential Revision: D9849812

fbshipit-source-id: d88973721da82040e1f29669acade6c883619ce8

src/__mocks__/init.js

@@ -1,10 +0,0 @@
-/**
- * Copyright 2018-present Facebook.
- * This source code is licensed under the MIT license found in the
- * LICENSE file in the root directory of this source tree.
- * @format
- */
-
-export default function init() {
-  // no-op
-}

src/index.js

@@ -14,10 +14,9 @@ export {SonarBasePlugin, SonarPlugin, SonarDevicePlugin} from './plugin.js';
 export {createTablePlugin} from './createTablePlugin.js';
 export {default as SonarSidebar} from './chrome/SonarSidebar.js';
 
+export * from './init.js';
+export {default} from './init.js';
+
 export {default as AndroidDevice} from './devices/AndroidDevice.js';
 export {default as Device} from './devices/BaseDevice.js';
 export {default as IOSDevice} from './devices/IOSDevice.js';
-
-import init from './init.js';
-
-init();

src/init.js

@@ -62,11 +62,10 @@ const AppFrame = () => (
   </TooltipProvider>
 );
 
-export default function init() {
+// $FlowFixMe: this element exists!
-  // $FlowFixMe: this element exists!
+ReactDOM.render(<AppFrame />, document.getElementById('root'));
-  ReactDOM.render(<AppFrame />, document.getElementById('root'));
+// $FlowFixMe: service workers exist!
-  // $FlowFixMe: service workers exist!
+navigator.serviceWorker
-  navigator.serviceWorker
   .register(
     process.env.NODE_ENV === 'production'
       ? path.join(__dirname, 'serviceWorker.js')
@@ -76,4 +75,3 @@ export default function init() {
     (r.installing || r.active).postMessage({precachedIcons});
   })
   .catch(console.error);
-}