Fix onMomentumScrollEnd dispatching on dismount

Summary:
This change is a follow-up to facebook#46277. 

This fixes two small issues:
1. `onMomentumScrollEnd` would dispatch when a scroll view is unmounted, regardless if the view was in motion or not
1. `scrollToOffset` would fire `onMomentumScrollEnd` regardless if animations were turned on or off

Changelog:
[iOS][Fixed] - Fixed `onMomentumScrollEnd` event not firing on unmount when the scroll view is not in motion

Differential Revision: D65559586

packages/react-native/React/Fabric/Mounting/ComponentViews/ScrollView/RCTScrollViewComponentView.mm

@@ -731,25 +731,29 @@ - (void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView
 - (void)scrollViewDidEndScrollingAnimation:(UIScrollView *)scrollView
 {
   [self _handleFinishedScrolling:scrollView];
+
+  if (!_eventEmitter) {
+    return;
+  }
+
+  static_cast<const ScrollViewEventEmitter &>(*_eventEmitter).onMomentumScrollEnd([self _scrollViewMetrics]);
 }
 
-- (void)didMoveToWindow
+- (void)willMoveToWindow:(UIWindow *)newWindow
 {
-  [super didMoveToWindow];
-
-  if (!self.window) {
+  [super willMoveToWindow:newWindow];
+  if (!newWindow) {
     // The view is being removed, ensure that the scroll end event is dispatched
     [self _handleScrollEndIfNeeded];
   }
 }
 
 - (void)_handleScrollEndIfNeeded
 {
-  if (_scrollView.isDecelerating || !_scrollView.isTracking) {
-    if (!_eventEmitter) {
-      return;
+  if (_scrollView.isDecelerating) {
+    if (_eventEmitter) {
+      static_cast<const ScrollViewEventEmitter &>(*_eventEmitter).onMomentumScrollEnd([self _scrollViewMetrics]);
     }
-    static_cast<const ScrollViewEventEmitter &>(*_eventEmitter).onMomentumScrollEnd([self _scrollViewMetrics]);
 
     [self _updateStateWithContentOffset];
     _isUserTriggeredScrolling = NO;
@@ -760,12 +764,6 @@ - (void)_handleFinishedScrolling:(UIScrollView *)scrollView
 {
   [self _forceDispatchNextScrollEvent];
   [self scrollViewDidScroll:scrollView];
-
-  if (!_eventEmitter) {
-    return;
-  }
-
-  static_cast<const ScrollViewEventEmitter &>(*_eventEmitter).onMomentumScrollEnd([self _scrollViewMetrics]);
   [self _updateStateWithContentOffset];
 }
 

packages/react-native/React/Views/ScrollView/RCTScrollView.m

@@ -860,16 +860,16 @@ - (void)scrollViewDidEndZooming:(UIScrollView *)scrollView withView:(UIView *)vi
   RCT_FORWARD_SCROLL_EVENT(scrollViewDidEndZooming : scrollView withView : view atScale : scale);
 }
 
-- (void)didMoveToWindow
+- (void)willMoveToWindow:(UIWindow *)newWindow
 {
-  [super didMoveToWindow];
-  if (self.window == nil) {
+  [super willMoveToWindow:newWindow];
+  if (!newWindow) {
     // Check if the ScrollView was in motion
-    if (_scrollView.isDecelerating || !_scrollView.isTracking) {
+    if (_scrollView.isDecelerating) {
       // Trigger the onMomentumScrollEnd event manually
       RCT_SEND_SCROLL_EVENT(onMomentumScrollEnd, nil);
-      // We can't use the RCT_FORWARD_SCROLL_EVENT here beacuse the `_cmd` parameter passed
-      // to `respondsToSelector` is the current method - so it will be `didMoveToWindow` - and not
+      // We can't use the RCT_FORWARD_SCROLL_EVENT here because the `_cmd` parameter passed
+      // to `respondsToSelector` is the current method - so it will be `willMoveToWindow` - and not
       // `scrollViewDidEndDecelerating` that is passed.
       for (NSObject<UIScrollViewDelegate> *scrollViewListener in _scrollListeners) {
         if ([scrollViewListener respondsToSelector:@selector(scrollViewDidEndDecelerating:)]) {