Cleanup mNativeChildren on react node cleanup.

Differential Revision: D2663443

fb-gh-sync-id: 7e6e7212103b738f6b6f535e54cc8b86e5def685

ReactAndroid/src/main/java/com/facebook/react/uimanager/NativeViewHierarchyOptimizer.java

@@ -90,6 +90,13 @@ public class NativeViewHierarchyOptimizer {
     }
   }
 
+  /**
+   * Handles native children cleanup when css node is removed from hierarchy
+   */
+  public static void handleRemoveNode(ReactShadowNode node) {
+    node.removeAllNativeChildren();
+  }
+
   /**
    * Handles an updateView call. If a view transitions from being layout-only to not (or vice-versa)
    * this could result in some number of additional createView and manageChildren calls. If the

ReactAndroid/src/main/java/com/facebook/react/uimanager/ReactShadowNode.java

@@ -137,20 +137,22 @@ public class ReactShadowNode extends CSSNode {
   }
 
   public void removeAllChildren() {
+    int decrease = 0;
     for (int i = getChildCount() - 1; i >= 0; i--) {
-      super.removeChildAt(i);
+      ReactShadowNode removed = (ReactShadowNode) super.removeChildAt(i);
+      decrease += removed.mIsLayoutOnly ? removed.mTotalNativeChildren : 1;
     }
     markUpdated();
 
-    updateNativeChildrenCountInParent(-mTotalNativeChildren);
-    mTotalNativeChildren = 0;
+    mTotalNativeChildren -= decrease;
+    updateNativeChildrenCountInParent(-decrease);
   }
 
   private void updateNativeChildrenCountInParent(int delta) {
     if (mIsLayoutOnly) {
       ReactShadowNode parent = getParent();
       while (parent != null) {
-        parent.mTotalNativeChildren -= delta;
+        parent.mTotalNativeChildren += delta;
         if (!parent.mIsLayoutOnly) {
           break;
         }
@@ -289,6 +291,15 @@ public class ReactShadowNode extends CSSNode {
     return removed;
   }
 
+  public void removeAllNativeChildren() {
+    if (mNativeChildren != null) {
+      for (int i = mNativeChildren.size() - 1; i >= 0; i--) {
+        mNativeChildren.get(i).mNativeParent = null;
+      }
+      mNativeChildren.clear();
+    }
+  }
+
   public int getNativeChildCount() {
     return mNativeChildren == null ? 0 : mNativeChildren.size();
   }

ReactAndroid/src/main/java/com/facebook/react/uimanager/UIManagerModule.java

@@ -399,17 +399,17 @@ public class UIManagerModule extends ReactContextBaseJavaModule implements
     }
 
     for (int i = 0; i < tagsToDelete.length; i++) {
-      removeCSSNode(tagsToDelete[i]);
+      removeShadowNode(mShadowNodeRegistry.getNode(tagsToDelete[i]));
     }
   }
 
-  private void removeCSSNode(int tag) {
-    ReactShadowNode node = mShadowNodeRegistry.getNode(tag);
-    mShadowNodeRegistry.removeNode(tag);
-    for (int i = node.getChildCount() - 1; i >= 0; i--) {
-      removeCSSNode(node.getChildAt(i).getReactTag());
+  private void removeShadowNode(ReactShadowNode nodeToRemove) {
+    mNativeViewHierarchyOptimizer.handleRemoveNode(nodeToRemove);
+    mShadowNodeRegistry.removeNode(nodeToRemove.getReactTag());
+    for (int i = nodeToRemove.getChildCount() - 1; i >= 0; i--) {
+      removeShadowNode(nodeToRemove.getChildAt(i));
     }
-    node.removeAllChildren();
+    nodeToRemove.removeAllChildren();
   }
 
   /**