fix: only intercept events with waiting handlers

Previously, NativeReanimatedModule::handleRawEvent would intercept all
events received by the event listener. This resulted in an issue where
onLayout would not fire in JS on the New Architecture.

Instead, only intercept events with waiting handlers. This prevents
asJSIValue from being called on the Reanimated event loop and allows
onLayout to bubble up in JS.

See
https://github.com/facebook/react-native/blob/v0.76.2/packages/react-native/ReactCommon/react/renderer/components/view/BaseViewEventEmitter.cpp#L82-L112,
which prevents onLayout from being dispatched more than once.

asJSIValue evaluates the lambda above in
https://github.com/facebook/react-native/blob/v0.76.2/packages/react-native/ReactCommon/react/renderer/core/ValueFactoryEventPayload.cpp#L16.

Fixes software-mansion#6684

apps/common-app/src/examples/RuntimeTests/RuntimeTestsExample.tsx

@@ -51,6 +51,8 @@ export default function RuntimeTestsExample() {
             require('./tests/core/useDerivedValue/chain.test');
 
             require('./tests/core/useSharedValue/animationsCompilerApi.test');
+
+            require('./tests/core/onLayout.test');
           },
         },
         {

apps/common-app/src/examples/RuntimeTests/tests/core/onLayout.test.tsx

@@ -0,0 +1,71 @@
+import { useEffect } from 'react';
+import type { LayoutChangeEvent } from 'react-native';
+import { StyleSheet, View } from 'react-native';
+import Animated, { runOnJS, runOnUI, useAnimatedStyle, useEvent, useSharedValue } from 'react-native-reanimated';
+import { describe, expect, notify, render, test, wait, waitForNotify } from '../../ReJest/RuntimeTestsApi';
+
+interface TestResult {
+  height: number;
+  animatedHandlerCalled: boolean;
+}
+
+const TestComponent = ({ result, notifyId }: { result: TestResult; notifyId: number }) => {
+  const height = useSharedValue(styles.smallBox.height);
+
+  const onLayout = (event: LayoutChangeEvent) => {
+    result.height = event.nativeEvent.layout.height;
+    if (result.height === 200) {
+      notify(`onLayout${notifyId}`);
+    }
+  };
+
+  const animatedStyle = useAnimatedStyle(() => {
+    return { height: height.value };
+  });
+
+  useEffect(() => {
+    runOnUI(() => {
+      height.value += 100;
+    })();
+  }, [height]);
+
+  const setAnimatedHandlerCalled = () => {
+    result.animatedHandlerCalled = true;
+    notify(`animatedOnLayout${notifyId}`);
+  };
+
+  const animatedOnLayout = useEvent(() => {
+    'worklet';
+    runOnJS(setAnimatedHandlerCalled)();
+  }, ['onLayout']);
+
+  return (
+    <View onLayout={onLayout}>
+      <Animated.View style={[styles.smallBox, animatedStyle]} onLayout={animatedOnLayout} />
+    </View>
+  );
+};
+
+describe('onLayout', () => {
+  test('is not intercepted when there are no registered event handlers', async () => {
+    const result = {} as TestResult;
+    await render(<TestComponent result={result} notifyId={1} />);
+    await Promise.race([waitForNotify('onLayout1'), wait(1000)]);
+    expect(result.height).toBe(200);
+  });
+
+  test('is dispatched to the registered event handler', async () => {
+    const result = {} as TestResult;
+    await render(<TestComponent result={result} notifyId={2} />);
+    await Promise.race([waitForNotify('animatedOnLayout2'), wait(1000)]);
+    expect(result.animatedHandlerCalled).toBe(true);
+  });
+});
+
+const styles = StyleSheet.create({
+  smallBox: {
+    width: 100,
+    height: 100,
+    backgroundColor: 'pink',
+  },
+});

packages/react-native-reanimated/Common/cpp/reanimated/NativeModules/ReanimatedModuleProxy.cpp

@@ -553,6 +553,11 @@ bool ReanimatedModuleProxy::handleRawEvent(
   if (eventType.rfind("top", 0) == 0) {
     eventType = "on" + eventType.substr(3);
   }
+
+  if (!isAnyHandlerWaitingForEvent(eventType, tag)) {
+    return false;
+  }
+
   jsi::Runtime &rt =
       workletsModuleProxy_->getUIWorkletRuntime()->getJSIRuntime();
   const auto &eventPayload = rawEvent.eventPayload;