Refactor access of ReactFeatureFlags from C++

Summary:
This diff is a follow up of D28360679 (https://github.com/facebook/react-native/commit/e3367354cc93f17b830ed8dc601dff5e87748dd1), here we refactor the access of ReactFeatureFlags from C++ to use methods instead of fields

changelog: [internal] internal

Reviewed By: JoshuaGross

Differential Revision: D28362066

fbshipit-source-id: caed5e7fddeb6c0d9846fb037152befa8f1ed5c2

ReactAndroid/src/main/java/com/facebook/react/config/ReactFeatureFlags.java

@@ -60,9 +60,6 @@ public class ReactFeatureFlags {
   /** Enables JS Responder in Fabric */
   public static boolean enableJSResponder = false;
 
-  /** Enables MapBuffer Serialization */
-  public static boolean mapBufferSerializationEnabled = false;
-
   /** An interface used to compute flags on demand. */
   public interface FlagProvider {
     boolean get();
@@ -75,6 +72,17 @@ public class ReactFeatureFlags {
     enableRuntimeExecutorFlushingProvider = provider;
   }
 
+  private static boolean mapBufferSerializationEnabled = false;
+
+  /** Enables or disables MapBuffer Serialization */
+  public static void setMapBufferSerializationEnabled(boolean enabled) {
+    mapBufferSerializationEnabled = enabled;
+  }
+
+  public static boolean isMapBufferSerializationEnabled() {
+    return mapBufferSerializationEnabled;
+  }
+
   public static boolean enableRuntimeExecutorFlushing() {
     if (enableRuntimeExecutorFlushingProvider != null) {
       return enableRuntimeExecutorFlushingProvider.get();

ReactAndroid/src/main/java/com/facebook/react/fabric/jni/Binding.cpp

@@ -453,6 +453,17 @@ void Binding::setConstraints(
   }
 }
 
+bool isMapBufferSerializationEnabled() {
+  static const auto reactFeatureFlagsJavaDescriptor =
+      jni::findClassStatic(Binding::ReactFeatureFlagsJavaDescriptor);
+  static const auto isMapBufferSerializationEnabledMethod =
+      reactFeatureFlagsJavaDescriptor->getStaticMethod<jboolean()>(
+          "isMapBufferSerializationEnabled");
+  bool value =
+      isMapBufferSerializationEnabledMethod(reactFeatureFlagsJavaDescriptor);
+  return value;
+}
+
 void Binding::installFabricUIManager(
     jni::alias_ref<JRuntimeExecutor::javaobject> runtimeExecutorHolder,
     jni::alias_ref<jobject> javaUIManager,
@@ -462,9 +473,6 @@ void Binding::installFabricUIManager(
     jni::alias_ref<jobject> reactNativeConfig) {
   SystraceSection s("FabricUIManagerBinding::installFabricUIManager");
 
-  static const auto reactFeatureFlagsJavaDescriptor =
-      jni::findClassStatic(Binding::ReactFeatureFlagsJavaDescriptor);
-
   std::shared_ptr<const ReactNativeConfig> config =
       std::make_shared<const ReactNativeConfigHolder>(reactNativeConfig);
 
@@ -533,14 +541,8 @@ void Binding::installFabricUIManager(
   // Keep reference to config object and cache some feature flags here
   reactNativeConfig_ = config;
 
-  static const auto mapBufferSerializationEnabledField =
-      reactFeatureFlagsJavaDescriptor->getStaticField<jboolean>(
-          "mapBufferSerializationEnabled");
-  bool mapBufferSerializationEnabled =
-      reactFeatureFlagsJavaDescriptor->getStaticFieldValue(
-          mapBufferSerializationEnabledField);
   contextContainer->insert(
-      "MapBufferSerializationEnabled", mapBufferSerializationEnabled);
+      "MapBufferSerializationEnabled", isMapBufferSerializationEnabled());
 
   disablePreallocateViews_ = reactNativeConfig_->getBool(
       "react_fabric:disabled_view_preallocation_android");

ReactAndroid/src/main/java/com/facebook/react/views/text/ReactTextViewManager.java

@@ -95,7 +95,7 @@ public class ReactTextViewManager
       return null;
     }
 
-    if (ReactFeatureFlags.mapBufferSerializationEnabled) {
+    if (ReactFeatureFlags.isMapBufferSerializationEnabled()) {
       ReadableMapBuffer stateMapBuffer = stateWrapper.getStatDataMapBuffer();
       if (stateMapBuffer != null) {
         return getReactTextUpdate(view, props, stateMapBuffer);