Transform fb-internal code within plugins

Summary: This diff changes flipper-pkg to allow using fb-internal code in plugins when they are packaged as standalone packages. It basically transforms fb-stubs/fb folders in plugins in the same way as for Flipper app.

Reviewed By: passy

Differential Revision: D27173406

fbshipit-source-id: 8ba97d5f57b5e276c19d13270a0d810873504add

desktop/babel-transformer/src/transform-plugin.ts

@@ -8,16 +8,13 @@
  */
 
 import {default as doTransform} from './transform';
-import {default as flipperEnv} from './flipper-env';
 
 const presets = [require('@babel/preset-react')];
 const plugins = [
   require('./electron-requires'),
   require('./plugin-flipper-requires'),
+  require('./fb-stubs'),
 ];
-if (flipperEnv.FLIPPER_FB) {
-  plugins.unshift(require('./fb-stubs'));
-}
 export default function transform({
   filename,
   options,