Clean up disableEventLoopOnBridgeless feature flag (#49065)

Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/49065

Changelog: [internal]

Cleaning up the flag because it's no longer necessary.

Reviewed By: sammy-SC

Differential Revision: D68892995

fbshipit-source-id: 4e0290bfb11181dc388e6590af1b82581588b9ee

packages/react-native/Libraries/Core/setUpTimers.js

@@ -10,9 +10,6 @@
 
 'use strict';
 
-const ReactNativeFeatureFlags = require('../../src/private/featureflags/ReactNativeFeatureFlags');
-const NativeReactNativeFeatureFlags =
-  require('../../src/private/featureflags/specs/NativeReactNativeFeatureFlags').default;
 const {polyfillGlobal} = require('../Utilities/PolyfillFunctions');
 
 if (__DEV__) {
@@ -21,19 +18,46 @@ if (__DEV__) {
   }
 }
 
-const isEventLoopEnabled = (() => {
-  if (NativeReactNativeFeatureFlags == null) {
-    return false;
-  }
-
-  return (
-    ReactNativeFeatureFlags.enableBridgelessArchitecture() &&
-    !ReactNativeFeatureFlags.disableEventLoopOnBridgeless()
-  );
-})();
-
 // In bridgeless mode, timers are host functions installed from cpp.
-if (global.RN$Bridgeless !== true) {
+if (global.RN$Bridgeless === true) {
+  // This is the flag that tells React to use `queueMicrotask` to batch state
+  // updates, instead of using the scheduler to schedule a regular task.
+  // We use a global variable because we don't currently have any other
+  // mechanism to pass feature flags from RN to React in OSS.
+  global.RN$enableMicrotasksInReact = true;
+
+  polyfillGlobal(
+    'queueMicrotask',
+    () =>
+      require('../../src/private/webapis/microtasks/specs/NativeMicrotasks')
+        .default.queueMicrotask,
+  );
+
+  // We shim the immediate APIs via `queueMicrotask` to maintain the backward
+  // compatibility.
+  polyfillGlobal(
+    'setImmediate',
+    () => require('./Timers/immediateShim').setImmediate,
+  );
+  polyfillGlobal(
+    'clearImmediate',
+    () => require('./Timers/immediateShim').clearImmediate,
+  );
+
+  polyfillGlobal(
+    'requestIdleCallback',
+    () =>
+      require('../../src/private/webapis/idlecallbacks/specs/NativeIdleCallbacks')
+        .default.requestIdleCallback,
+  );
+
+  polyfillGlobal(
+    'cancelIdleCallback',
+    () =>
+      require('../../src/private/webapis/idlecallbacks/specs/NativeIdleCallbacks')
+        .default.cancelIdleCallback,
+  );
+} else {
   /**
    * Set up timers.
    * You can use this module directly, or just require InitializeCore.
@@ -59,50 +83,7 @@ if (global.RN$Bridgeless !== true) {
   defineLazyTimer('cancelAnimationFrame');
   defineLazyTimer('requestIdleCallback');
   defineLazyTimer('cancelIdleCallback');
-} else if (isEventLoopEnabled) {
-  polyfillGlobal(
-    'requestIdleCallback',
-    () =>
-      require('../../src/private/webapis/idlecallbacks/specs/NativeIdleCallbacks')
-        .default.requestIdleCallback,
-  );
 
-  polyfillGlobal(
-    'cancelIdleCallback',
-    () =>
-      require('../../src/private/webapis/idlecallbacks/specs/NativeIdleCallbacks')
-        .default.cancelIdleCallback,
-  );
-}
-
-// We need to check if the native module is available before accessing the
-// feature flag, because otherwise the API would throw an error in the legacy
-// architecture in OSS, where the native module isn't available.
-if (isEventLoopEnabled) {
-  // This is the flag that tells React to use `queueMicrotask` to batch state
-  // updates, instead of using the scheduler to schedule a regular task.
-  // We use a global variable because we don't currently have any other
-  // mechanism to pass feature flags from RN to React in OSS.
-  global.RN$enableMicrotasksInReact = true;
-
-  polyfillGlobal(
-    'queueMicrotask',
-    () =>
-      require('../../src/private/webapis/microtasks/specs/NativeMicrotasks')
-        .default.queueMicrotask,
-  );
-
-  // We shim the immediate APIs via `queueMicrotask` to maintain the backward
-  // compatibility.
-  polyfillGlobal(
-    'setImmediate',
-    () => require('./Timers/immediateShim').setImmediate,
-  );
-  polyfillGlobal(
-    'clearImmediate',
-    () => require('./Timers/immediateShim').clearImmediate,
-  );
-} else {
   // Polyfill it with promise (regardless it's polyfilled or native) otherwise.
   polyfillGlobal(
     'queueMicrotask',
@@ -112,14 +93,12 @@ if (isEventLoopEnabled) {
   // When promise was polyfilled hence is queued to the RN microtask queue,
   // we polyfill the immediate APIs as aliases to the ReactNativeMicrotask APIs.
   // Note that in bridgeless mode, immediate APIs are installed from cpp.
-  if (global.RN$Bridgeless !== true) {
-    polyfillGlobal(
-      'setImmediate',
-      () => require('./Timers/JSTimers').default.queueReactNativeMicrotask,
-    );
-    polyfillGlobal(
-      'clearImmediate',
-      () => require('./Timers/JSTimers').default.clearReactNativeMicrotask,
-    );
-  }
+  polyfillGlobal(
+    'setImmediate',
+    () => require('./Timers/JSTimers').default.queueReactNativeMicrotask,
+  );
+  polyfillGlobal(
+    'clearImmediate',
+    () => require('./Timers/JSTimers').default.clearReactNativeMicrotask,
+  );
 }

packages/react-native/ReactCommon/react/nativemodule/featureflags/NativeReactNativeFeatureFlags.cpp

@@ -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<<6b314d87b09e65d8c70a0d3f4caf953a>>
+ * @generated SignedSource<<0d5df5cac07efb95bfd5f0984f960a0b>>
  */
 
 /**
@@ -49,13 +49,6 @@ bool NativeReactNativeFeatureFlags::commonTestFlagWithoutNativeImplementation(
   return false;
 }
 
-bool NativeReactNativeFeatureFlags::disableEventLoopOnBridgeless(
-    jsi::Runtime& /*runtime*/) {
-  // This flag is configured with `skipNativeAPI: true`.
-  // TODO(T204838867): Implement support for optional methods in C++ TM codegen and remove the method definition altogether.
-  return false;
-}
-
 bool NativeReactNativeFeatureFlags::disableMountItemReorderingAndroid(
     jsi::Runtime& /*runtime*/) {
   return ReactNativeFeatureFlags::disableMountItemReorderingAndroid();

packages/react-native/ReactCommon/react/nativemodule/featureflags/NativeReactNativeFeatureFlags.h

@@ -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<<3b3ce0cfc8578f517393b89dc76a9aac>>
+ * @generated SignedSource<<44a75d78e4910acb405e79e9953f563a>>
  */
 
 /**
@@ -39,8 +39,6 @@ class NativeReactNativeFeatureFlags
 
   bool commonTestFlagWithoutNativeImplementation(jsi::Runtime& runtime);
 
-  bool disableEventLoopOnBridgeless(jsi::Runtime& runtime);
-
   bool disableMountItemReorderingAndroid(jsi::Runtime& runtime);
 
   bool enableAccumulatedUpdatesInRawPropsAndroid(jsi::Runtime& runtime);

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

@@ -57,16 +57,6 @@ const testDefinitions: FeatureFlagDefinitions = {
 const definitions: FeatureFlagDefinitions = {
   common: {
     ...testDefinitions.common,
-    disableEventLoopOnBridgeless: {
-      defaultValue: false,
-      metadata: {
-        description:
-          'The bridgeless architecture enables the event loop by default. This feature flag allows us to force disabling it in specific instances.',
-        expectedReleaseValue: true,
-        purpose: 'release',
-      },
-      skipNativeAPI: true,
-    },
     disableMountItemReorderingAndroid: {
       defaultValue: false,
       metadata: {

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<<fdb43dd2f218d9e7d30946ee2f895619>>
+ * @generated SignedSource<<7d66477e7b024c551085f068a6445014>>
  * @flow strict
  */
 
@@ -50,7 +50,6 @@ export type ReactNativeFeatureFlags = $ReadOnly<{
   ...ReactNativeFeatureFlagsJsOnly,
   commonTestFlag: Getter<boolean>,
   commonTestFlagWithoutNativeImplementation: Getter<boolean>,
-  disableEventLoopOnBridgeless: Getter<boolean>,
   disableMountItemReorderingAndroid: Getter<boolean>,
   enableAccumulatedUpdatesInRawPropsAndroid: Getter<boolean>,
   enableBridgelessArchitecture: Getter<boolean>,
@@ -176,10 +175,6 @@ export const commonTestFlag: Getter<boolean> = createNativeFlagGetter('commonTes
  * Common flag for testing (without native implementation). Do NOT modify.
  */
 export const commonTestFlagWithoutNativeImplementation: Getter<boolean> = createNativeFlagGetter('commonTestFlagWithoutNativeImplementation', false, true);
-/**
- * The bridgeless architecture enables the event loop by default. This feature flag allows us to force disabling it in specific instances.
- */
-export const disableEventLoopOnBridgeless: Getter<boolean> = createNativeFlagGetter('disableEventLoopOnBridgeless', false, true);
 /**
  * Prevent FabricMountingManager from reordering mountitems, which may lead to invalid state on the UI thread
  */

packages/react-native/src/private/featureflags/specs/NativeReactNativeFeatureFlags.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<<c23785c59894d331228bece04fe3a868>>
+ * @generated SignedSource<<73d10e1985377162b75ee60e5bcad8dd>>
  * @flow strict
  */
 
@@ -25,7 +25,6 @@ import * as TurboModuleRegistry from '../../../../Libraries/TurboModule/TurboMod
 export interface Spec extends TurboModule {
   +commonTestFlag?: () => boolean;
   +commonTestFlagWithoutNativeImplementation?: () => boolean;
-  +disableEventLoopOnBridgeless?: () => boolean;
   +disableMountItemReorderingAndroid?: () => boolean;
   +enableAccumulatedUpdatesInRawPropsAndroid?: () => boolean;
   +enableBridgelessArchitecture?: () => boolean;