Add @nullable to ScrollView getChildVisibleRect offset parameter

Summary:
The `offset` parameter in `getChildVisibleRect` overrides was missing the
`Nullable` annotation. The Android framework contract for
`ViewGroup.getChildVisibleRect(View, Rect, Point)` allows `offset` to be null,
and `View.getGlobalVisibleRect(Rect)` legitimately passes null. The `Nullsafe`
instrumentation injected a non-null assertion that crashed when null was passed.

Changelog:
[Android][Fixed] - Fix NullPointerException in ScrollView `getChildVisibleRect` when `offset` is null

Differential Revision: D107507935

Author: cortinico

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

@@ -1054,7 +1054,7 @@ public void getClippingRect(Rect outClippingRect) {
   }
 
   @Override
-  public boolean getChildVisibleRect(View child, Rect r, android.graphics.Point offset) {
+  public boolean getChildVisibleRect(View child, Rect r, @Nullable android.graphics.Point offset) {
     return super.getChildVisibleRect(child, r, offset);
   }
 

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

@@ -807,7 +807,7 @@ public void getClippingRect(Rect outClippingRect) {
   }
 
   @Override
-  public boolean getChildVisibleRect(View child, Rect r, android.graphics.Point offset) {
+  public boolean getChildVisibleRect(View child, Rect r, @Nullable android.graphics.Point offset) {
     return super.getChildVisibleRect(child, r, offset);
   }
 

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

@@ -799,7 +799,7 @@ public void getClippingRect(Rect outClippingRect) {
   }
 
   @Override
-  public boolean getChildVisibleRect(View child, Rect r, android.graphics.Point offset) {
+  public boolean getChildVisibleRect(View child, Rect r, @Nullable android.graphics.Point offset) {
     return super.getChildVisibleRect(child, r, offset);
   }