修正子测量项切换异常

lib/process/items/top_item.dart

@@ -65,6 +65,7 @@ abstract class TopMeasureItem<T extends MeasureItemFeature>
   @override
   void switchChild(int index) {
     if (index == _childIndex) return;
+    workingChild.finishOnce();
     _childIndex = index;
     if (workingChild.measuredFeatures.isNotEmpty) {
       isNeedRedraw = true;