Pass on the bundle name rather than the ID when getting transform opt…

…ions

Summary:
public

This is needed to bring numerical module IDs back.

The numerical ID of the main module will always be `0` and is therefore of no use when used as conditional. We have to pass on the name, which will be preserved, when requesting transform options.

Reviewed By: martinbigio

Differential Revision: D2855106

fb-gh-sync-id: f9bc40e753b1b283ce0b00068e3c9964a541ad9b

packager/react-packager/src/Bundler/index.js

@@ -190,6 +190,7 @@ class Bundler {
     return this.getDependencies(entryFile, isDev, platform).then((response) => {
       Activity.endEvent(findEventId);
       bundle.setMainModuleId(response.mainModuleId);
+      bundle.setMainModuleName(response.mainModuleId);
       transformEventId = Activity.startEvent('transform');
 
       const moduleSystemDeps = includeSystemDependencies
@@ -396,7 +397,7 @@ class Bundler {
       return this._transformer.loadFileAndTransform(
         path.resolve(module.path),
         this._getTransformOptions(
-          {bundleEntry: bundle.getMainModuleId(), modulePath: module.path},
+          {bundleEntry: bundle.getMainModuleName(), modulePath: module.path},
           {hot: hot},
         ),
       );