Add enableMountingCoordinatorPullModelAndroid feature flag

Summary:
Adds the `enableMountingCoordinatorPullModelAndroid` experiment flag (default off) that gates the Android pull-model mounting migration. Config entry plus regenerated accessors only — no behavior change.

## Changelog:
[Android] [Added] - Add `enableMountingCoordinatorPullModelAndroid` feature flag

Differential Revision: D112309049

Author: Bartlomiej Bloniarz

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/internal/featureflags/ReactNativeFeatureFlags.kt

@@ -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<<df3f81d0083a8ebe9d0fbcb86e652405>>
+ * @generated SignedSource<<8508c768e49199737ce5fd1071ca1d68>>
  */
 
 /**
@@ -252,6 +252,12 @@ public object ReactNativeFeatureFlags {
   @JvmStatic
   public fun enableModuleArgumentNSNullConversionIOS(): Boolean = accessor.enableModuleArgumentNSNullConversionIOS()
 
+  /**
+   * When enabled, Android mounts transactions with the pull model (like iOS): the commit thread no longer pulls and builds the mount batch in schedulerShouldRenderTransactions. Instead the UI thread pulls the transaction itself via a PullTransactionMountItem enqueued in the MountItemDispatcher, builds the IntBufferBatchMountItem, and applies it synchronously. Implies rawProps accumulation (enableAccumulatedUpdatesInRawPropsAndroid behavior).
+   */
+  @JvmStatic
+  public fun enableMountingCoordinatorPullModelAndroid(): Boolean = accessor.enableMountingCoordinatorPullModelAndroid()
+
   /**
    * Enables the MutationObserver Web API in React Native.
    */

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/internal/featureflags/ReactNativeFeatureFlagsCxxAccessor.kt

@@ -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<<c31110405f1c9cd5ae0627fb114585a6>>
+ * @generated SignedSource<<eeb2c4625ae5039dc087f364713050fe>>
  */
 
 /**
@@ -57,6 +57,7 @@ internal class ReactNativeFeatureFlagsCxxAccessor : ReactNativeFeatureFlagsAcces
   private var enableLayoutAnimationsOnAndroidCache: Boolean? = null
   private var enableLayoutAnimationsOnIOSCache: Boolean? = null
   private var enableModuleArgumentNSNullConversionIOSCache: Boolean? = null
+  private var enableMountingCoordinatorPullModelAndroidCache: Boolean? = null
   private var enableMutationObserverByDefaultCache: Boolean? = null
   private var enableNativeCSSParsingCache: Boolean? = null
   private var enableNetworkEventReportingCache: Boolean? = null
@@ -441,6 +442,15 @@ internal class ReactNativeFeatureFlagsCxxAccessor : ReactNativeFeatureFlagsAcces
     return cached
   }
 
+  override fun enableMountingCoordinatorPullModelAndroid(): Boolean {
+    var cached = enableMountingCoordinatorPullModelAndroidCache
+    if (cached == null) {
+      cached = ReactNativeFeatureFlagsCxxInterop.enableMountingCoordinatorPullModelAndroid()
+      enableMountingCoordinatorPullModelAndroidCache = cached
+    }
+    return cached
+  }
+
   override fun enableMutationObserverByDefault(): Boolean {
     var cached = enableMutationObserverByDefaultCache
     if (cached == null) {

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/internal/featureflags/ReactNativeFeatureFlagsCxxInterop.kt

@@ -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<<87b76f5c2af82462dc66c7721cd66ac4>>
+ * @generated SignedSource<<9a171a03d15885e64b84f03442b304b4>>
  */
 
 /**
@@ -102,6 +102,8 @@ public object ReactNativeFeatureFlagsCxxInterop {
 
   @DoNotStrip @JvmStatic public external fun enableModuleArgumentNSNullConversionIOS(): Boolean
 
+  @DoNotStrip @JvmStatic public external fun enableMountingCoordinatorPullModelAndroid(): Boolean
+
   @DoNotStrip @JvmStatic public external fun enableMutationObserverByDefault(): Boolean
 
   @DoNotStrip @JvmStatic public external fun enableNativeCSSParsing(): Boolean

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/internal/featureflags/ReactNativeFeatureFlagsDefaults.kt

@@ -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<<8a117541421f413e517e1be1acf8be7d>>
+ * @generated SignedSource<<4fd762a8e3ab6de1276a15368075f40c>>
  */
 
 /**
@@ -97,6 +97,8 @@ public open class ReactNativeFeatureFlagsDefaults : ReactNativeFeatureFlagsProvi
 
   override fun enableModuleArgumentNSNullConversionIOS(): Boolean = false
 
+  override fun enableMountingCoordinatorPullModelAndroid(): Boolean = false
+
   override fun enableMutationObserverByDefault(): Boolean = false
 
   override fun enableNativeCSSParsing(): Boolean = false

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/internal/featureflags/ReactNativeFeatureFlagsLocalAccessor.kt

@@ -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<<9a2806b3934d130010954a92a7b48e0f>>
+ * @generated SignedSource<<4a4a234004196595b5fb2949bd91f9c4>>
  */
 
 /**
@@ -61,6 +61,7 @@ internal class ReactNativeFeatureFlagsLocalAccessor : ReactNativeFeatureFlagsAcc
   private var enableLayoutAnimationsOnAndroidCache: Boolean? = null
   private var enableLayoutAnimationsOnIOSCache: Boolean? = null
   private var enableModuleArgumentNSNullConversionIOSCache: Boolean? = null
+  private var enableMountingCoordinatorPullModelAndroidCache: Boolean? = null
   private var enableMutationObserverByDefaultCache: Boolean? = null
   private var enableNativeCSSParsingCache: Boolean? = null
   private var enableNetworkEventReportingCache: Boolean? = null
@@ -482,6 +483,16 @@ internal class ReactNativeFeatureFlagsLocalAccessor : ReactNativeFeatureFlagsAcc
     return cached
   }
 
+  override fun enableMountingCoordinatorPullModelAndroid(): Boolean {
+    var cached = enableMountingCoordinatorPullModelAndroidCache
+    if (cached == null) {
+      cached = currentProvider.enableMountingCoordinatorPullModelAndroid()
+      accessedFeatureFlags.add("enableMountingCoordinatorPullModelAndroid")
+      enableMountingCoordinatorPullModelAndroidCache = cached
+    }
+    return cached
+  }
+
   override fun enableMutationObserverByDefault(): Boolean {
     var cached = enableMutationObserverByDefaultCache
     if (cached == null) {

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/internal/featureflags/ReactNativeFeatureFlagsProvider.kt

@@ -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<<49c76b8072c1bd29135086c9e0a5da2f>>
+ * @generated SignedSource<<0b4bf7de06ad677b0868640c98ff0aa9>>
  */
 
 /**
@@ -97,6 +97,8 @@ public interface ReactNativeFeatureFlagsProvider {
 
   @DoNotStrip public fun enableModuleArgumentNSNullConversionIOS(): Boolean
 
+  @DoNotStrip public fun enableMountingCoordinatorPullModelAndroid(): Boolean
+
   @DoNotStrip public fun enableMutationObserverByDefault(): Boolean
 
   @DoNotStrip public fun enableNativeCSSParsing(): Boolean

packages/react-native/ReactAndroid/src/main/jni/react/featureflags/JReactNativeFeatureFlagsCxxInterop.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<<42f1901c8b7cb568cc761a791991a333>>
+ * @generated SignedSource<<a795068a8d53ac4385bf77461792fd70>>
  */
 
 /**
@@ -261,6 +261,12 @@ class ReactNativeFeatureFlagsJavaProvider
     return method(javaProvider_);
   }
 
+  bool enableMountingCoordinatorPullModelAndroid() override {
+    static const auto method =
+        getReactNativeFeatureFlagsProviderJavaClass()->getMethod<jboolean()>("enableMountingCoordinatorPullModelAndroid");
+    return method(javaProvider_);
+  }
+
   bool enableMutationObserverByDefault() override {
     static const auto method =
         getReactNativeFeatureFlagsProviderJavaClass()->getMethod<jboolean()>("enableMutationObserverByDefault");
@@ -750,6 +756,11 @@ bool JReactNativeFeatureFlagsCxxInterop::enableModuleArgumentNSNullConversionIOS
   return ReactNativeFeatureFlags::enableModuleArgumentNSNullConversionIOS();
 }
 
+bool JReactNativeFeatureFlagsCxxInterop::enableMountingCoordinatorPullModelAndroid(
+    facebook::jni::alias_ref<JReactNativeFeatureFlagsCxxInterop> /*unused*/) {
+  return ReactNativeFeatureFlags::enableMountingCoordinatorPullModelAndroid();
+}
+
 bool JReactNativeFeatureFlagsCxxInterop::enableMutationObserverByDefault(
     facebook::jni::alias_ref<JReactNativeFeatureFlagsCxxInterop> /*unused*/) {
   return ReactNativeFeatureFlags::enableMutationObserverByDefault();
@@ -1142,6 +1153,9 @@ void JReactNativeFeatureFlagsCxxInterop::registerNatives() {
       makeNativeMethod(
         "enableModuleArgumentNSNullConversionIOS",
         JReactNativeFeatureFlagsCxxInterop::enableModuleArgumentNSNullConversionIOS),
+      makeNativeMethod(
+        "enableMountingCoordinatorPullModelAndroid",
+        JReactNativeFeatureFlagsCxxInterop::enableMountingCoordinatorPullModelAndroid),
       makeNativeMethod(
         "enableMutationObserverByDefault",
         JReactNativeFeatureFlagsCxxInterop::enableMutationObserverByDefault),

packages/react-native/ReactAndroid/src/main/jni/react/featureflags/JReactNativeFeatureFlagsCxxInterop.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<<9967d87b794ba46797ed78a845683dc7>>
+ * @generated SignedSource<<5ffd2340bcfdeb6919f215f494040fb9>>
  */
 
 /**
@@ -141,6 +141,9 @@ class JReactNativeFeatureFlagsCxxInterop
   static bool enableModuleArgumentNSNullConversionIOS(
     facebook::jni::alias_ref<JReactNativeFeatureFlagsCxxInterop>);
 
+  static bool enableMountingCoordinatorPullModelAndroid(
+    facebook::jni::alias_ref<JReactNativeFeatureFlagsCxxInterop>);
+
   static bool enableMutationObserverByDefault(
     facebook::jni::alias_ref<JReactNativeFeatureFlagsCxxInterop>);
 

packages/react-native/ReactCommon/react/featureflags/ReactNativeFeatureFlags.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<<6f2362e9844cab731ca01e4af563fde9>>
+ * @generated SignedSource<<28cc44042e02c3521b40c6c2ba005888>>
  */
 
 /**
@@ -174,6 +174,10 @@ bool ReactNativeFeatureFlags::enableModuleArgumentNSNullConversionIOS() {
   return getAccessor().enableModuleArgumentNSNullConversionIOS();
 }
 
+bool ReactNativeFeatureFlags::enableMountingCoordinatorPullModelAndroid() {
+  return getAccessor().enableMountingCoordinatorPullModelAndroid();
+}
+
 bool ReactNativeFeatureFlags::enableMutationObserverByDefault() {
   return getAccessor().enableMutationObserverByDefault();
 }

packages/react-native/ReactCommon/react/featureflags/ReactNativeFeatureFlags.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<<f871b2203c86dd7f25640cd3a6ea7d00>>
+ * @generated SignedSource<<66d7e8a85d0925fc03660ac22f2fb500>>
  */
 
 /**
@@ -224,6 +224,11 @@ class ReactNativeFeatureFlags {
    */
   RN_EXPORT static bool enableModuleArgumentNSNullConversionIOS();
 
+  /**
+   * When enabled, Android mounts transactions with the pull model (like iOS): the commit thread no longer pulls and builds the mount batch in schedulerShouldRenderTransactions. Instead the UI thread pulls the transaction itself via a PullTransactionMountItem enqueued in the MountItemDispatcher, builds the IntBufferBatchMountItem, and applies it synchronously. Implies rawProps accumulation (enableAccumulatedUpdatesInRawPropsAndroid behavior).
+   */
+  RN_EXPORT static bool enableMountingCoordinatorPullModelAndroid();
+
   /**
    * Enables the MutationObserver Web API in React Native.
    */