[Flight] Fix webpack plugin to use chunk groups (#20421)

Author: gaearon

packages/react-server-dom-webpack/src/ReactFlightWebpackPlugin.js

@@ -170,26 +170,29 @@ export default class ReactFlightWebpackPlugin {
 
     compiler.hooks.emit.tap(PLUGIN_NAME, compilation => {
       const json = {};
-      compilation.chunks.forEach(chunk => {
-        chunk.getModules().forEach(mod => {
-          // TOOD: Hook into deps instead of the target module.
-          // That way we know by the type of dep whether to include.
-          // It also resolves conflicts when the same module is in multiple chunks.
-          if (!/\.client\.js$/.test(mod.resource)) {
-            return;
-          }
-          const moduleExports = {};
-          ['', '*'].concat(mod.buildMeta.providedExports).forEach(name => {
-            moduleExports[name] = {
-              id: mod.id,
-              chunks: chunk