Remove animatedShouldUseSingleOp feature flag (#57364)

Summary:

The single-op batching guard now lives entirely in `NativeAnimatedHelper`, where `isSingleOpBatching` is gated on `Platform.OS === 'android'`, `queueAndExecuteBatchedOperations` being available, and `!cxxNativeAnimatedEnabled()`. The `animatedShouldUseSingleOp` flag defaulted to `true` and no longer carries any of that logic, so it is fully redundant. Remove the flag from the config, drop its now-vestigial term from `isSingleOpBatching` in both `NativeAnimatedHelper.js` and the macOS variant, and regenerate `ReactNativeFeatureFlags.js`.

This is behavior-preserving: with the flag at its default `true`, `isSingleOpBatching` evaluates identically to before on every platform.

Changelog:
[Internal]

Reviewed By: javache

Differential Revision: D109570192

Author: zeyap

packages/react-native/scripts/featureflags/ReactNativeFeatureFlags.config.js

@@ -981,17 +981,6 @@ const definitions: FeatureFlagDefinitions = {
       },
       ossReleaseStage: 'none',
     },
-    animatedShouldUseSingleOp: {
-      defaultValue: true,
-      metadata: {
-        dateAdded: '2024-02-05',
-        description:
-          'Enables an experimental mega-operation for Animated.js that replaces many calls to native with a single call into native, to reduce JSI/JNI traffic.',
-        expectedReleaseValue: true,
-        purpose: 'experimentation',
-      },
-      ossReleaseStage: 'none',
-    },
     deferFlatListFocusChangeRenderUpdate: {
       defaultValue: false,
       metadata: {

packages/react-native/src/private/animated/NativeAnimatedHelper.js

@@ -56,7 +56,6 @@ const singleOpQueue: Array<unknown> = [];
 const isSingleOpBatching =
   Platform.OS === 'android' &&
   NativeAnimatedModule?.queueAndExecuteBatchedOperations != null &&
-  ReactNativeFeatureFlags.animatedShouldUseSingleOp() &&
   !ReactNativeFeatureFlags.cxxNativeAnimatedEnabled();
 let flushQueueImmediate = null;
 

packages/react-native/src/private/featureflags/ReactNativeFeatureFlags.js

@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @generated SignedSource<<5e80ae1ef75d1fbf51fd94cd5495157f>>
+ * @generated SignedSource<<7b617acfec15f418c1d9fca60fdb3dd5>>
  * @flow strict
  * @noformat
  */
@@ -32,7 +32,6 @@ export type ReactNativeFeatureFlagsJsOnly = Readonly<{
   animatedDeferStartOfTimingAnimations: Getter<boolean>,
   animatedForceNativeDriver: Getter<boolean>,
   animatedShouldSyncValueBeforeStartCallback: Getter<boolean>,
-  animatedShouldUseSingleOp: Getter<boolean>,
   deferFlatListFocusChangeRenderUpdate: Getter<boolean>,
   enableImperativeEvents: Getter<boolean>,
   enableNativeEventTargetEventDispatching: Getter<boolean>,
@@ -155,11 +154,6 @@ export const animatedForceNativeDriver: Getter<boolean> = createJavaScriptFlagGe
  */
 export const animatedShouldSyncValueBeforeStartCallback: Getter<boolean> = createJavaScriptFlagGetter('animatedShouldSyncValueBeforeStartCallback', true);
 
-/**
- * Enables an experimental mega-operation for Animated.js that replaces many calls to native with a single call into native, to reduce JSI/JNI traffic.
- */
-export const animatedShouldUseSingleOp: Getter<boolean> = createJavaScriptFlagGetter('animatedShouldUseSingleOp', true);
-
 /**
  * Use the deferred cell render update mechanism for focus change in FlatList.
  */