Deprecate com/facebook/react/config/ReactFeatureFlags (#42718)

Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/42718

Deprecate com/facebook/react/config/ReactFeatureFlags, to be replaced by com.facebook.react.internal.featureflags.ReactNativeFeatureFlags

changelog: [internal] internal

Reviewed By: NickGerleman

Differential Revision: D53199655

fbshipit-source-id: 32bdc526e377ff70e2df3c97a259066a25180231

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/config/ReactFeatureFlags.java

@@ -17,6 +17,7 @@ import com.facebook.react.common.build.ReactBuildConfig;
  *
  * <p>These values are safe defaults and should not require manual changes.
  */
+@Deprecated(since = "Use com.facebook.react.internal.featureflags.ReactNativeFeatureFlags instead.")
 @DoNotStripAny
 public class ReactFeatureFlags {
   /**

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/defaults/DefaultNewArchitectureEntryPoint.kt

@@ -25,6 +25,7 @@ import com.facebook.react.config.ReactFeatureFlags
 object DefaultNewArchitectureEntryPoint {
   @JvmStatic
   @JvmOverloads
+  @Suppress("DEPRECATION")
   fun load(
       turboModulesEnabled: Boolean = true,
       fabricEnabled: Boolean = true,

packages/rn-tester/android/app/src/main/java/com/facebook/react/uiapp/RNTesterApplication.kt

@@ -49,6 +49,7 @@ class RNTesterApplication : Application(), ReactApplication {
                   name: String,
                   reactContext: ReactApplicationContext
               ): NativeModule? {
+                @Suppress("DEPRECATION")
                 if (!ReactFeatureFlags.useTurboModules) {
                   return null
                 }
@@ -66,6 +67,7 @@ class RNTesterApplication : Application(), ReactApplication {
               // modules.
               override fun getReactModuleInfoProvider(): ReactModuleInfoProvider =
                   ReactModuleInfoProvider {
+                    @Suppress("DEPRECATION")
                     if (ReactFeatureFlags.useTurboModules) {
                       mapOf(
                           SampleTurboModule.NAME to
@@ -77,6 +79,7 @@ class RNTesterApplication : Application(), ReactApplication {
                                   false, // isCxxModule
                                   true // isTurboModule
                                   ),
+
                           SampleLegacyModule.NAME to
                               ReactModuleInfo(
                                   SampleLegacyModule.NAME,
@@ -86,6 +89,7 @@ class RNTesterApplication : Application(), ReactApplication {
                                   false, // isCxxModule
                                   false // isTurboModule
                                   ))
+
                     } else {
                       emptyMap()
                     }