Mark FPS listener in ScrollViews as final, avoid reset in initView

Summary:
`mFpsListener` is injected via `ReactHorizontalScrollView`'s constructor and should live for the lifetime of the view. However, it was declared as a mutable field and nulled in `initView()`, which is called both during construction and when the view is recycled in a virtualized list. After recycling, `isScrollPerfLoggingEnabled()` returned false because `mFpsListener` was null, silently disabling FPS performance tracking for the rest of that view instance's lifecycle.

The fix moves `mFpsListener` to a `final` field initialized in the constructor, and removes the `mFpsListener = null` assignment from `initView()`. Applied to `ReactScrollView`, `ReactHorizontalScrollView`, and `ReactNestedScrollView`.

This is a safe change because both view managers are instantiated with a single instance of FPS listener, so recycled view instances will always reference the same FPS listener instance.

Changelog:
[Android][Fixed] - Fix FPS performance listener being cleared on ScrollView recycle

Differential Revision: D102359747

Author: Abbondanzo

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/views/scroll/ReactHorizontalScrollView.java

@@ -101,6 +101,7 @@ public class ReactHorizontalScrollView extends HorizontalScrollView
   private final VelocityHelper mVelocityHelper = new VelocityHelper();
   private final Rect mTempRect = new Rect();
   private final ValueAnimator DEFAULT_FLING_ANIMATOR = ObjectAnimator.ofInt(this, "scrollX", 0, 0);
+  private final @Nullable FpsListener mFpsListener;
 
   private Rect mOverflowInset = new Rect();
   private @Nullable VirtualViewContainerState mVirtualViewContainerState;
@@ -113,7 +114,6 @@ public class ReactHorizontalScrollView extends HorizontalScrollView
   private boolean mRemoveClippedSubviews;
   private boolean mScrollEnabled = true;
   private boolean mSendMomentumEvents;
-  private @Nullable FpsListener mFpsListener = null;
   private @Nullable String mScrollPerfTag;
   private @Nullable Drawable mEndBackground;
   private int mEndFillColor = Color.TRANSPARENT;
@@ -177,7 +177,6 @@ private void initView() {
     mRemoveClippedSubviews = false;
     mScrollEnabled = true;
     mSendMomentumEvents = false;
-    mFpsListener = null;
     mScrollPerfTag = null;
     mEndBackground = null;
     mEndFillColor = Color.TRANSPARENT;

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/views/scroll/ReactNestedScrollView.java

@@ -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<<41d03f4948562c0fae870a660e6e1eac>>
+ * @generated SignedSource<<2aa191314924bd0f969fba0e64b86142>>
  */
 
 /**
@@ -106,6 +106,7 @@ class ReactNestedScrollView extends NestedScrollView
   private final VelocityHelper mVelocityHelper = new VelocityHelper();
   private final Rect mTempRect = new Rect();
   private final ValueAnimator DEFAULT_FLING_ANIMATOR = ObjectAnimator.ofInt(this, "scrollY", 0, 0);
+  private final @Nullable FpsListener mFpsListener;
 
   private Rect mOverflowInset;
   private @Nullable VirtualViewContainerState mVirtualViewContainerState;
@@ -118,7 +119,6 @@ class ReactNestedScrollView extends NestedScrollView
   private boolean mRemoveClippedSubviews;
   private boolean mScrollEnabled;
   private boolean mSendMomentumEvents;
-  private @Nullable FpsListener mFpsListener;
   private @Nullable String mScrollPerfTag;
   private @Nullable Drawable mEndBackground;
   private int mEndFillColor;

packages/react-native/ReactAndroid/src/main/java/com/facebook/react/views/scroll/ReactScrollView.java

@@ -98,6 +98,7 @@ public class ReactScrollView extends ScrollView
   private final VelocityHelper mVelocityHelper = new VelocityHelper();
   private final Rect mTempRect = new Rect();
   private final ValueAnimator DEFAULT_FLING_ANIMATOR = ObjectAnimator.ofInt(this, "scrollY", 0, 0);
+  private final @Nullable FpsListener mFpsListener;
 
   private Rect mOverflowInset;
   private @Nullable VirtualViewContainerState mVirtualViewContainerState;
@@ -110,7 +111,6 @@ public class ReactScrollView extends ScrollView
   private boolean mRemoveClippedSubviews;
   private boolean mScrollEnabled;
   private boolean mSendMomentumEvents;
-  private @Nullable FpsListener mFpsListener;
   private @Nullable String mScrollPerfTag;
   private @Nullable Drawable mEndBackground;
   private int mEndFillColor;