react-native-codegen: Enable C++ TurboModule generation in OpenSource builds (facebook#35211)

Summary:
Pull Request resolved: facebook#35211

This enables the generation of C++ TurboModule specs in addition to existing Java/ObjC ones.

An example is shown in facebook#35138

Changelog: [Internal]

Differential Revision: D41057630

fbshipit-source-id: 74d2d1f24bd0dd156cf5268d08af458393e574e3

Author: christophpurrer

scripts/codegen/__tests__/generate-specs-cli-executor-test.js

@@ -26,7 +26,7 @@ describe('generateSpec', () => {
     const outputDirectory = normalize('app/ios/build/generated/ios');
     const libraryName = 'library';
     const packageName = 'com.library';
-    const generators = ['componentsIOS', 'modulesIOS'];
+    const generators = ['componentsIOS', 'modulesIOS', 'modulesCxx'];
 
     jest.mock('fs', () => ({
       readFileSync: (path, encoding) => {

scripts/codegen/generate-specs-cli-executor.js

@@ -17,16 +17,16 @@ const RNCodegen = utils.getCodegen();
 
 const GENERATORS = {
   all: {
-    android: ['componentsAndroid', 'modulesAndroid'],
-    ios: ['componentsIOS', 'modulesIOS'],
+    android: ['componentsAndroid', 'modulesAndroid', 'modulesCxx'],
+    ios: ['componentsIOS', 'modulesIOS', 'modulesCxx'],
   },
   components: {
     android: ['componentsAndroid'],
     ios: ['componentsIOS'],
   },
   modules: {
-    android: ['modulesAndroid'],
-    ios: ['modulesIOS'],
+    android: ['modulesAndroid', 'modulesCxx'],
+    ios: ['modulesIOS', 'modulesCxx'],
   },
 };