Add support for legacy UIManager in UIManagerHelper (#41206)

Summary:

Root cause: Currently Bridgeless only support FabricUIManager and the legacy UIManager is not supported

Next steps: check for other places where legacy UIManager is not supported

Changelog:
[Android][Changed] - Bridgeless: Add support for legacy UIManager in UIManagerHelper

Reviewed By: cortinico

Differential Revision: D50694805

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/uimanager/UIManagerHelper.java

@@ -22,9 +22,9 @@
 import com.facebook.react.bridge.ReactNoCrashSoftException;
 import com.facebook.react.bridge.ReactSoftExceptionLogger;
 import com.facebook.react.bridge.UIManager;
+import com.facebook.react.config.ReactFeatureFlags;
 import com.facebook.react.uimanager.common.UIManagerType;
 import com.facebook.react.uimanager.events.EventDispatcher;
-import com.facebook.react.uimanager.events.EventDispatcherProvider;
 
 /** Helper class for {@link UIManager}. */
 public class UIManagerHelper {
@@ -53,13 +53,19 @@ private static UIManager getUIManager(
       @UIManagerType int uiManagerType,
       boolean returnNullIfCatalystIsInactive) {
     if (context.isBridgeless()) {
-      @Nullable UIManager uiManager = (UIManager) context.getJSIModule(JSIModuleType.UIManager);
+      UIManager uiManager = null;
+      if (uiManagerType == FABRIC) {
+        uiManager = (UIManager) context.getJSIModule(JSIModuleType.UIManager);
+      } else if (ReactFeatureFlags.unstable_useFabricInterop) {
+        // When Fabric Interop is enabled in Bridgeless mode, enable the legacy UIManager
+        uiManager = context.getNativeModule(UIManagerModule.class);
+      }
+
       if (uiManager == null) {
         ReactSoftExceptionLogger.logSoftException(
             TAG,
             new ReactNoCrashSoftException(
                 "Cannot get UIManager because the instance hasn't been initialized yet."));
-        return null;
       }
       return uiManager;
     }
@@ -118,13 +124,6 @@ public static EventDispatcher getEventDispatcherForReactTag(ReactContext context
   @Nullable
   public static EventDispatcher getEventDispatcher(
       ReactContext context, @UIManagerType int uiManagerType) {
-    // TODO T67518514 Clean this up once we migrate everything over to bridgeless mode
-    if (context.isBridgeless()) {
-      if (context instanceof ThemedReactContext) {
-        context = ((ThemedReactContext) context).getReactApplicationContext();
-      }
-      return ((EventDispatcherProvider) context).getEventDispatcher();
-    }
     UIManager uiManager = getUIManager(context, uiManagerType, false);
     if (uiManager == null) {
       ReactSoftExceptionLogger.logSoftException(