Fix assertion failure when reordering two dimensional children (flutter#141504)

It fixes assertion failure due to unstable state of children list during reordering in `RenderTwoDimensionalViewport.parentDataOf`. This changes the assertion to check debug orphan list and `keepAlive` bucket in addition to children list to determine whether child belongs to this render object or not.

- Fixes flutter#141101

Author: Amir-P

packages/flutter/lib/src/widgets/two_dimensional_viewport.dart

@@ -779,8 +779,11 @@ abstract class RenderTwoDimensionalViewport extends RenderBox implements RenderA
   /// Children must have a [ParentData] of type
   /// [TwoDimensionalViewportParentData], or a subclass thereof.
   @protected
+  @mustCallSuper
   TwoDimensionalViewportParentData parentDataOf(RenderBox child) {
-    assert(_children.containsValue(child));
+    assert(_children.containsValue(child) ||
+        _keepAliveBucket.containsValue(child) ||
+        _debugOrphans!.contains(child));
     return child.parentData! as TwoDimensionalViewportParentData;
   }
 

packages/flutter/test/widgets/two_dimensional_utils.dart

@@ -195,7 +195,7 @@ class RenderSimpleBuilderTableViewport extends RenderTwoDimensionalViewport {
 
   @override
   TestExtendedParentData parentDataOf(RenderBox child) {
-    return child.parentData! as TestExtendedParentData;
+    return super.parentDataOf(child) as TestExtendedParentData;
   }
 
   @override

packages/flutter/test/widgets/two_dimensional_viewport_test.dart

@@ -2711,6 +2711,54 @@ void main() {
         );
       });
     });
+
+    testWidgets('correctly reorders children and wont throw assertion failure',
+        (WidgetTester tester) async {
+      final TwoDimensionalChildBuilderDelegate delegate1 =
+          TwoDimensionalChildBuilderDelegate(
+              maxXIndex: 5,
+              maxYIndex: 5,
+              addAutomaticKeepAlives: false,
+              addRepaintBoundaries: false,
+              builder: (BuildContext context, ChildVicinity vicinity) {
+                ValueKey<int>? key;
+                if (vicinity == const ChildVicinity(xIndex: 1, yIndex: 1)) {
+                  key = const ValueKey<int>(1);
+                } else if (vicinity ==
+                    const ChildVicinity(xIndex: 1, yIndex: 2)) {
+                  key = const ValueKey<int>(2);
+                }
+                return SizedBox.square(key: key, dimension: 200);
+              });
+      final TwoDimensionalChildBuilderDelegate delegate2 =
+          TwoDimensionalChildBuilderDelegate(
+              maxXIndex: 5,
+              maxYIndex: 5,
+              addAutomaticKeepAlives: false,
+              addRepaintBoundaries: false,
+              builder: (BuildContext context, ChildVicinity vicinity) {
+                ValueKey<int>? key;
+                if (vicinity == const ChildVicinity(xIndex: 0, yIndex: 0)) {
+                  key = const ValueKey<int>(1);
+                } else if (vicinity ==
+                    const ChildVicinity(xIndex: 1, yIndex: 1)) {
+                  key = const ValueKey<int>(2);
+                }
+                return SizedBox.square(key: key, dimension: 200);
+              });
+      addTearDown(delegate1.dispose);
+      addTearDown(delegate2.dispose);
+
+      await tester.pumpWidget(simpleBuilderTest(delegate: delegate1));
+      expect(tester.getRect(find.byKey(const ValueKey<int>(1))),
+          const Rect.fromLTWH(200.0, 200.0, 200.0, 200.0));
+      await tester.pumpWidget(simpleBuilderTest(delegate: delegate2));
+      expect(tester.getRect(find.byKey(const ValueKey<int>(1))),
+          const Rect.fromLTWH(0.0, 0.0, 200.0, 200.0));
+      await tester.pumpWidget(simpleBuilderTest(delegate: delegate1));
+      expect(tester.getRect(find.byKey(const ValueKey<int>(1))),
+          const Rect.fromLTWH(200.0, 200.0, 200.0, 200.0));
+    }, variant: TargetPlatformVariant.all());
   });
 }